Wednesday, July 18, 2018

Xenology - An Introduction to the Scientific Study of Extraterrestrial Life, Intelligence, and Civilization

Part III ♦ ET Civlizations

© 1979 Robert A. Freitas Jr. All Rights Reserved

  Chapter 15 ♦ Energy and Culture   
15.0 Energy and Culture
leslie white


Science of culture

It is only in the last decade or two that a true "science of culture" has begun to emerge. The systematic and rational treatment of human civilization as a process has passed in and out of vogue on several occasions during this century. There is considerable hostility in many quarters to the basic notion that cultures must conform to certain basic rules of construction, expression, and evolution, and frequently this has led to what one "hard science" science-fiction writer grumblingly describes as "a couple of anthropologists sitting in a semi-dark room and dictating great thoughts."2857

The process of civilization,
as of life, is negentropic.

But progress is now being made. One of the best efforts to date has been by Dr. Leslie White, a social anthropologist at the University of Michigan in Ann Arbor. In his book The Science of Culture (1969), he presents the beginnings of a theory of culture which is utterly fascinating from a xenological point of view.36

Three subsystems of culture

Dr. White suggests that all civilization is founded upon, and determined by, the sources of energy which it controls. The processes of society are in some sense "powered" by energy. He goes on to propose that any cultural system — human or extraterrestrial — may be divided into three fundamental subsystems; the technological, the sociological, and the ideological.

The functioning of culture as a whole therefore rests
upon and is determined by the amount of energy
harnessed and by the way in which it is put to work.
  • The technological subsystem is comprised of all the physical, mechanical, biological, and chemical instruments that are available to sentient members of the culture, for the purpose of manipulating matter. Technology is the sum total of a race's material environment, together with the instruments of manipulation and the techniques of their use.
  • The sociological subsystem consists of the various interpersonal relation ships between members of a culture. These may be expressed in collective as well as individual patterns of behavior, psychology, and modes of social conduct.
  • The ideological subsystem is made up primarily of symbolic articulations of ideas, beliefs, attitudes and knowledge. Cultural ideology encompasses the philosophy, artistic forms, patterns of logic, and epistomologies peculiar to a given society.

Figure 15.1 The Cultural Pyramid Theory of Civilization36

figure 15 1 cultural pyramid theory med
The cultural pyramid

How are these three cultural subsystems interrelated? According to Dr. White, the rigors of existence (the demand for food, shelter, protection, companionship) can only be met by resorting to technology. This technology may be extremely primitive — stone knives, bearskins, and a blazing campfire — but it is technology nevertheless. Social systems are subsidiary, described by White as "the organized effort of {sentient} beings in the use of the instruments of subsistence, offense and defense, and protection." Philosophical systems are the means by which technological and social experience finds its interpretation. In fact, there is a type of philosophy appropriate to any conceivable class of technology:

A pastoral, agricultural, metallurgical, industrial, or military technology will each find its corresponding expression in philosophy. One type of technology will find expression in the philosophy of totemism, another in astrology or quantum mechanics. … Social systems are therefore determined by technological systems, and philosophies and the arts express experience as it is defined by technology and refracted by social systems.36

We may imagine a pyramid, grounded in energy and constructed in three tiers (Figure 15.1).

Each tier represents one of the basic cultural subsystems which, in the aggregate, comprise the entire civilization. Leslie White elaborates on the idea:

We may view a cultural system as a series of three horizontal strata: the technological layer on the bottom, the philosophical on the top, the sociological stratum in between. These positions express their respective roles in the culture process. The technological system is basic and primary. Social systems are functions of technologies; and philosophies express technological forces and reflect social systems. The technological factor is therefore the determinant of a cultural system as a whole. It determines the form of social systems, and technology and society together determine the content and orientation of philosophy. This is not to say, of course, that social systems do not condition the operation of technologies, or that social and technological systems are not affected by philosophies. They do and are. But to condition is one thing; to determine, quite another.36

Intelligence and technology

As Freeman Dyson has often pointed out, a sharp distinction may be drawn between intelligence and technology. One needn‘t imply the other. That is, it's easy to imagine a society of intelligent lifeforms with little or no particular interest in advanced technology.80 But White's cultural subsystems must be given broad interpretation if they are to be applied to extraterrestrial races. "Technology," for instance, may have an organic rather than an inorganic basis.389 Instead of mechanical devices and machines, alien technology may consist of trained animals, slave labor, architectural coral and so forth.

"Technology," for instance, may have
an organic rather than an inorganic basis.
Instead of mechanical devices and machines,
alien technology may consist of trained animals,
slave labor, architectural coral and so forth.

How does this relate to energy?

The process of civilization is negentropic

The business of life is to accumulate information and complexity. This is accomplished by using energy to suck in data from the natural environment and build the elaborate structure represented by a living organism. The process of culture, though on a different plane, serves an analogous, function. By absorbing information from the social environment, an aggregation of organisms can build an intricate social structure by the proper application of energy and tools. Just as a living being is a highly complex arrangement of individual molecules, so is a society an intricate association of individual organisms. The process of civilization, as of life, is negentropic.

Cultural development, in the very widest sense, thus is a product both of energy and of technology:

Culture confronts us as an elaborate thermodynamic, mechanical system. By means of technological instruments energy is harnessed and put to work. Social and philosophic systems are both adjuncts and expressions of this technologic process. The functioning of culture as a whole therefore rests upon and is determined by the amount of energy harnessed and by the way in which it is put to work.36

The remainder of this chapter is devoted to the general evolution and utilization of sources of energy by extraterrestrial cultures and races anywhere in the Universe. The following four chapters detail many of the possible alien technological advances, thus completing our discussion of the foundation of Dr. White's three-tiered "cultural pyramid." The last four chapters in Part Three consider the more speculative — and perhaps more interesting — social and philosophical upper strata we may discover among extraterrestrial civilizations elsewhere in space.

15.1 Type I Civilizations: Planetary Cultures
Planetary cultures

Figure 15.2 The Night-time View of the Eastern

United States, as Seen from Space2603


The thermal burden of energy usage on Earth is a planetary,
not local, issue.

A primitive intelligent alien race, slowly evolving and spreading across the face of its native world, eventually will discover and utilize a wide variety of elementary energy supplies. In the beginning, such creatures would rely mainly on natural sources such as hot springs, fires set by lightning, and their own muscle power.

But soon their intelligence, and the Principle of Economy, would impel them to develop new and easier ways to generate and harness energy. They‘d learn to set their own fires, and how to control them. Animals might be harnessed for transportation, hauling, and agricultural activities. Better fuels, such as coal or natural oil secured from local tar pits, would replace wood in campfires.

Incubation period of growth

On our own home planet, this early period was marked by a relatively slow growth in worldwide energy usage. The increase amounted to no more than perhaps 0.3% per year, a doubling time of about 200 years. The speed at which basic resources could be pressed into service, with primitive technology and finite manpower, was extremely limited. Such an early "incubation period" of leisurely growth should be common during the first stages of cultural evolution on any world.

It is entirely possible that ETs on some planets may call a halt, or even reverse, this upward trend in energy consumption. This does not necessarily imply an immediate halt to all technological development — for instance, the culture may simply be shifting its attention from energy-intensive projects to information-intensive ones. However, it does place rather stringent limitations upon the material achievements to which the society may aspire. Without abundant energy, an economy of scarcity management is virtually inevitable.

Finding this prospect rather unattractive, and driven onward by the curiosity and aggressiveness that enabled them to take dominion over their world, many intelligent extraterrestrial races would seek to further improve both the sources and the distribution of power.

On Earth, the widespread initiation of fossil fuel burning (stored solar energy) provided a powerful new source of abundant energy. While great effort was required to harvest tiny amounts of power from wind and water, a tiny bit of oil or natural gas went a long way. In addition, steam and electricity came into their own during the last two centuries of human history. There was getting to be an abundance of raw energy, powerful ways of harnessing it to perform useful work, and efficient means of transmitting it over great distances. The dawn of global culture was at hand (Figure 15.2).

The dawn of global culture

In the last two centuries, humanity has
maintained a 3% per year growth rate in energy
consumption, a full order of magnitude above
the early stages of cultural evolution on Earth.

In only two thousand years, mankind's
per capita energy production has leapt from
about 30 watts/person in ancient times
to nearly 2000 watts/person today.

By 2300 A.D. humanity will be generating
as much energy artificially as is received at
the planet's surface from its sun

In the last two centuries, humanity has maintained a 3% per year growth rate in energy consumption, a full order of magnitude above the early stages of cultural evolution on Earth. The doubling time is now measured in decades rather than in centuries. Let's see exactly what this means.

It is believed that the Roman Empire, at the height of its expansive construction and military activities, annually consumed power at a rate roughly equivalent to 3 × 109 watts (1 watt = 1 joule/second). Nearly two millenia later, humanity has increased its energy usage a thousandfold. By 1975, global power consumption reached about 7 × 1012 watts. In only two thousand years, mankind's per capita energy production has leapt from about 30 watts/person in ancient times to nearly 2000 watts/person today.

Xenologists want to know whether or not energy usage will also increase exponentially among alien cultures, as it appears to have done here. Perhaps more interesting and germaine, however, is the following related query: Are there any limits to growth, assuming the ETs adopt an expansionist philosophy?

Three factors delimiting accessible energy

It turns out, not surprisingly perhaps, that there do exist very definite limits to growth for any culture that remains confined to the surface of a single planet. There are three fundamental factors which delimit the quantities of energy accessible to a sentient race:

  • Availability
  • Efficiency
  • Planetary carrying capacity
Availability

It is estimated that if all the deuterium
in Earth's seas were collected and burned in
fusion power stations, it would supply all
our energy needs at the present rate of
consumption for the next 5-10 billion years
— roughly the expected lifetime of Sol.

Our first consideration is the availability of a given energy resource. In general, sources compete with one another depending on their relative scarcity or abundance. To take one trivial example, an alien culture located on a world with little water and strong winds might be expected to place greater emphasis on the development of windmills rather than waterwheels or dams.

A corollary to the fact that a civilization is planetbound is the inevitable finiteness of all resources. There is only so much wind, water, geothermal steam, wood, fossil and nuclear fuels at the surface of a world. Once the population of an extraterrestrial culture has expanded to the point where these resources are in danger of exhaustion, the civilization faces drastic modification, degeneration, or possibly even extinction on a global scale. Such is the early and quite predictable result of sole reliance upon nonrenewable sources of energy.

Nuclear fusion

Fortunately, there exist two sources which should be available to all ET societies and which are virtually inexhaustible. First, there is nuclear fusion. This involves mashing together two atoms (usually of hydrogen) which yields a single heavier atom plus lots of energy. About one hydrogen in every 6000 in ordinary seawater is deuterium, the most likely hydrogen isotope to be used in controlled thermonuclear power generation. It is estimated that if all the deuterium in Earth's seas were collected and burned in fusion power stations, it would supply all our energy needs at the present rate of consumption for the next 5-10 billion years — roughly the expected lifetime of Sol.

An alien civilization that opts for fusion power may expect to have enough energy to endure over geological timescales provided there is no growth. If there are oceans of water sufficient to spawn life, there will probably also be enough deuterium to provide all "Type I"* planetbound cultures with virtually inexhaustible energy.**

Solar power

The other major energy source available to planetary cultures is solar power. Unless blocked by a thick cloud cover, filtered out by the atmosphere, or attenuated by great distances, radiative energy from the stellar primary can serve as a bountiful and virtually infinite "renewable" source of power. Since stars in habitable solar systems may be expected to have lifetimes measured in eons, a Type I extraterrestrial civilization could again expect a long healthy existence before its energy supply ran out.

So on the question of availability, a large-scale Type I planetary culture should ultimately benefit most from either deuterium fusion power or solar fusion power.


* Dr. N.S. Kardashev, a well-known Russian astrophysicist currently associated with the Institute for Cosmic Research at the Soviet Academy of Sciences in Moscow, devised a particularly fruitful classification scheme which includes all conceivable ET civilizations and is based on system-wide energy consumption.1320 However, Kardashev limited his analysis to the energy available for the purpose of interstellar communication between alien cultures. In this book the original concepts are broadened to provide a general taxonomy for all extra-terrestrial civilizations — whether communicative or not.

** Cultures native to planets with ammonia or methane oceans similarly will have an abundance of deuterium fusion fuel at their disposal. Inhabitants of worlds with sulfur or liquid carbon dioxide seas will not be so fortunate.

Efficiency

Table 15.1 Conversion of Matter into Energy:

A Comparison of Efficiencies

table 15 1 conversion of matter into energy 350

The second consideration involves the question of the efficiency of the particular energy resource chosen. Since the technology of a civilization limited to the surface of a single world will ultimately experience severe restrictions on its finite resources, it is important to make the best use possible of what little is available.

All energy, whether from fusion, fission,
or chemical reactions, ultimately derives
from the conversion of a tiny bit
of matter into heat, light, sound, etc.

Earlier in this century, the late Albert Einstein demonstrated that mass and energy are interchangeable. According to the famous E = mc2, a given amount of matter (m) is exactly equivalent to a certain quantity of energy (E). (The constant of proportionality, c2, is the speed of light, squared.) All energy, whether from fusion, fission, or chemical reactions, ultimately derives from the conversion of a tiny bit of matter into heat, light, sound, etc.

Conversion of matter into energy

If their civilization is to long endure, ETs must find the most efficient means for converting mass into energy. Table 15-l provides a representative sampling of various common and theoretical energy sources available to Type I planetary cultures on any world in our Galaxy. In each case the efficiency is calculated, based on the fraction of matter which is changed into usable energy. The most efficient is "total conversion" (100% of the matter goes to energy), but it is difficult to imagine the cheap production of sufficient quantities of antimatter to make this process competitive with thermonuclear fusion.

Indeed, fusion appears to be the most efficient energy generation technique for which the fuel is exceedingly abundant. Once again, both deuterium fusion power and solar fusion power qualify as most efficient. So on the basis of the two factors we‘ve looked at, it is a pretty sure bet that advanced Type I alien cultures will adopt either or both of these techniques.

Planetary carrying capacity

Figure 15.3 Curve of Growth of Technological Energy Usage

for a Typical Emergent Type I Civilization: Humanity

figure 15 3 curve of growth of technological energy usage 500px

But even using the most efficient, abundant sources of energy, planetbound societies cannot continue to expand indefinitely. This is because of the third critical limiting factor: Planetary carrying capacity. The history of our own planet is typical.

In the past century, world energy production has escalated at an average rate of 3% per annum. Approximately every twenty years, human power consumption doubles. In 1975 we used 7 × 1012 watts. If the historical 3% growth rate is maintained, then by the year 2300 A.D., mankind's energy budget will be up to 2 × 1017 watts. Why is this significant? Simply because 2 × 1017 watts is also the total power received from Sol on planet Earth. To sum up, by 2300 A.D. humanity will be generating as much energy artificially as is received at the planet's surface from its sun (Figure 15.3).

Growth of technological energy usage

We will then face the most critical "energy crisis" in the history of Earth. Rather than a crisis of scarcity, however, it will be a crisis of overabundance.

All forms of energy — electrical, thermal, mechanical, nuclear — ultimately return to the biosphere in a single degraded form: Heat. Such thermal pollution can rapidly reach catastrophic proportions. As more and more energy — heat — is liberated at the planetary surface, the global temperature begins to rise and the precarious energy balance of the biosphere begins to suffer irreversible damage.

Most experts believe that irreversible destruction
of environmental equilibrium would occur at far lower
levels of energy production. Conservatives usually
draw the line at the photosynthetic energy limit,
or the total solar energy fixed by green plants
worldwide. This is only about 4 × 1013 watts.
Hypsithermal catastrophe

At what point in the development of a Type I civilization will this ultimate "hypsithermal catastrophe" occur? Certainly by the time artificial energy production equals total solar influx, the planet will have suffered serious ecological damage.29 Earth, for instance, would no longer be inhabitable by humans, our lush green world converted into a stewing, steamy hellhole much like Venus. Most experts believe that irreversible destruction of environmental equilibrium would occur at far lower levels of energy production. Conservatives usually draw the line at the photosynthetic energy limit, or the total solar energy fixed by green plants worldwide. This is only about 4 × 1013 watts.

The best guess seems to be about 1% of the total solar influx as the critical limit.29, 688 This is about 5% of the energy stored in Earth's hydrosphere, and would probably be sufficient to melt the polar icecaps and thoroughly disrupt the entire ecology. On planets with smaller oceans, or with non-water oceans, the climatic turnover point might occur far sooner.

We estimate, therefore, that the maximum upper limit of artificial energy generation for any Type I planetary culture limited to a single world in our Galaxy is roughly 1015 watts.

15.2 Type II Civilizations: Stellar Cultures
i s shklovskii


Spacefaring cultures

In the earliest stages of social evolution, alien societies will be pretty much restricted to the surface of their planet. Type I civilizations are defined as those which consume power at the carrying capacity of the planet. Such cultures are limited to the energy obtainable on a single world.

We've seen that planetbound societies can have a long and healthy existence, and may expect to survive for eons barring some unusual major global catastrophe of some kind. But this imposes rather stringent limits to growth on planetary cultures. The price that must be paid for stability and long-term survival on the limited surface of a single world is energetic stasis. This may well lead to cultural stagnation.

Alien races may discover that the only escape from this trap is to move out into space. A Type I society will remain one forever, until and unless it becomes spacefaring.

Space industrialization

With the first flights of the American space shuttle, humanity has taken the first tentative step in the evolution from a planetbound Type I to a spacefaring Type II stellar culture. In the centuries to come, space industrialization will proceed with vigor as man becomes more aware of the countless ad-vantages of space-based manufacturing. Of these, the two most highly significant benefits for long-term, large-scale heavy industrial development are vast size and vast energy.

Flimsy constructions many tens of kilometers
in diameter are possible even with present-day
human technology!
Giant artifacts

First, whether in orbit around the home planet or swinging freely in circumsolar territory, physical stresses on material structures are always minute. For this reason, giant artifacts which would be impossible on the surface of a planet will be commonplace in space. Flimsy constructions many tens of kilometers in diameter are possible even with present-day human technology! Huge factories and physical plants may be assembled. Once manufacturing activities in orbit reach a point of relative self-sufficiency — a kind of economic "critical mass" — further expansion will be breathtakingly rapid.

Energy abundance

Second, habitats lofted to planetary or solar orbit will find a vast abundance of solar energy. A single world intercepts only a tiny fraction of the entire solar output, less than one one-billionth of the total. But the spacefaring Type II civilization can collect energy from anywhere on a theoretical spherical shell surrounding the central star — a potential energy preserve perhaps ten or eleven orders of magnitude greater than that available at the surface of the home world.

Dyson Sphere


An almost solid sphere of artifacts envelops
the sun, absorbing and directing each watt
to the purposes of the gargantuan
interplanetary industrial complex.

Dyson Sphere

The swarm of technological artifacts orbiting in successive shells around the primary will grow thick as development proceeds. These space factories and habitats ultimately will enclose and capture virtually the entire stellar energy output. This amounts to what xenologists usually call a "Dyson Sphere." Originated by Freeman Dyson at Princeton, the Dyson Sphere is the end result of full space industrialization by a Type II civilization. An almost solid sphere of artifacts envelops the sun, absorbing and directing each watt to the purposes of the gargantuan interplanetary industrial complex.

Dyson limit

But even solar energy is not limitless. All spacefaring cultures ultimately must run afoul of the "Dyson limit" — the sum total of all energy emitted by the home star. This is, in some sense, the "carrying capacity" of the entire solar system. Even if the jovian planets are disassembled and cannibalized for fusionable hydrogen, the Dyson limit cannot be much exceeded without sacrificing cultural longevity (e.g., by cannibalizing the home star itself).

How long will it take for an intelligent species to evolve from a planet-bound Type I culture to a spacefaring Type II civilization pressing fitfully against the Dyson limit?

Transition time-scale

A typical sun of the habitable variety illuminates alien transsolar space with about 1026 watts of power. Assuming a modest 3% per year growth rate in the interplanetary industrial complex, a Type I civilization (1015 watts) could make the transition to a fully industrialized Type II civilization (1026 watts) in a mere 900 years. Even if we take the incredibly conservative primitive growth rate of 0.3% per year, the transition is accomplished in just 9000 years — long by human standards but only the wink of an eye on geological and evolutionary timescales. We know that it has taken humanity about 10,000 years since the invention of agriculture and basic toolmaking to build a planetary culture, so the estimates above are certainly reasonable.

15.3 Type III Civilizations: Galactic Cultures
v a razin


Beyond the Dyson limit

Extraterrestrial societies, frustrated by the Dyson limit, may push outward still further, spreading their influence from stellar system to stellar system across their galaxy. In time, such a culture — comprised of many millions or even billions of Type II civilizations — may come to dominate the entire galactic corpus. Such a "Type III civilization" could be capable of diverting the power of a hundred billion thermonuclear stellar furnaces to its own cooperative purposes.

Type III culture at its peak
would command the power
of a hundred billion suns

Synergistic interaction

The nature of galactic community is very much dependent upon the peculiar aspects of the physical environment. Interstellar distances are vastly greater than interplanetary ones. While a Type II culture might evolve along the lines suggested above (filling transsolar space with the artifacts of industrialization and commercial development), the endless empty regions between stars are unlikely ever to be similarly occupied. Rather, the typical Type III civilization most likely will consist of a collection of Type II civilizations. A synergistic interaction will take place giving rise to a hybrid galactic culture, a melting pot of countless millions of worlds.

A galactic community may resemble a mammoth
archipelago of solar system societies, a multitude
of civilized islands separated by the vastness of
the oceans of space.
This is within the limits even of a lowly Type I
society such as our own. The 300-meter dish at
Arecibo, Puerto Rico, could communicate with its
twin located almost anywhere in the Milky Way.
Archipelago of solar systems

A galactic community may resemble a mammoth archipelago of solar system societies, a multitude of civilized islands separated by the vastness of the oceans of space. Despite this wide dispersion, a Type III culture at its peak would command the power of a hundred billion suns — upwards of 1037 watts. Longevity could be measured in hundreds of eons.

Transition time-scale

The time required for galactic civilization to expand to its full potential depends on the assumptions we make. Xenologists hesitate to use a simple exponential extrapolation of the 3% growth rate, because the spatial scale of interstellar expansion is qualitatively different from planetary and interplanetary scales.

If we assume, for example, that the galaxy is teeming with sentient life forms, and that none have advanced beyond the Type II stage of development, then direct interstellar colonization by any one race requires war and imperialism and so is probably not a viable ethical alternative. In this case, cultural unification will be accomplished by an exchange of valuable information and ideas using radio waves or laser beacons whose messages travel at the speed of light. This is within the limits even of a lowly Type I society such as our own. The 300-meter dish at Arecibo, Puerto Rico, could communicate with its twin located almost anywhere in the Milky Way. Clearly, Type II cultures will have the energy to transmit vast quantities of data to their interstellar neighbors.

Cultural integration

The typical spiral galaxy spans perhaps 100,000 light-years, so the fastest news can travel from one end to the other is about 100,000 years. If we allow for search and acquisition (first you have to find your neighbors), and for the probability that at least ten exchanges would likely be necessary for cultural integration and homogenization,15 then we find that a unified polyspecies galactic civilization might conceivably begin to take form after only about a million years.*

United galactic culture

On the other hand, what if we assume that the galaxy in question is not teeming with life? Perhaps it consists of a few scattered Type I societies, an occasional and very rare emergent Type II culture, with the great bulk of all galactic real estate consisting primarily of undeveloped planetary systems. In this case, preemptive colonization efforts by one of the Type II societies might be appropriate. This ultimately will lead to a "united" galactic culture under the leadership of a single sentient race.

While this period seems fantastically long by
human standards, we must remember that
the potential lifespan of a galactic civilization
should run into the hundreds of billions of years.
Colonization

How long might this take? We might imagine that a highly industrialized stellar culture could launch a large interstellar fleet of colony starships to nearby suns. They'd take along the basic implements which would enable them to set up a thriving planetary civilization. It may require 103-10years to tame and populate the new solar system, and to build another budding Type II community around the new star. Only after the position of the original colony was secure could the pioneers seriously consider the possibility of dispatching a colonization armada of their own.

The subjugation of the galaxy would thus proceed in a series of waves, pulsing at thousand-year intervals. The alien race could sail the sea of stars at an average rate of perhaps 0.001 light-years of penetration per year. A single aggressive species could dominate an entire galaxy in less than ten million years.

While this period seems fantastically long by human standards, we must remember that the potential lifespan of a galactic civilization should run into the hundreds of billions of years. The initial colonization period represents less than 0.01% of the total lifetime of the Type III monospecies culture in question.


* While it's true that the use of tachyon communications might greatly reduce this "cultural incubation" time, it is also true that the faster a tachyon beam travels, the lower is its maximum theoretical bit rate.3119 The advantages of speed thus may be outweighed by the disadvantage of lower information transferral.

15.4 Type IV Civilizations: Universal Cultures
oliver goldsmith


Herculean projects

  • Changing structure of spacetime
  • Slowing or reversal of entropy
  • Colonization of other universes

Finally, we must mention the possibility of Type IV civilizations, intergalactic cultures spanning the breadth and width of the Universe.

Such a community would commingle the individual cultures of a billion galactic associations, and might command the power of a billion trillion suns — perhaps 1047 watts.

A universal civilization could seriously consider attempting such truly Herculean projects as changing the structure of spacetime, the deliberate slowing or reversal of entropy in our universe to achieve ultimate immortality, or the colonization of other universes (if they exist).

  Chapter 16 ♦ Xenobiotechnology   
16.0 Xenobiotechnology
paul anderson


People are so constituted
that they would rather be
alive than dead.

Survival instinct

Sir Peter B. Medawar, British Nobelist in medicine and a pioneer in immunology and transplantation research, once remarked that "people are so constituted that they would rather be alive than dead."1646 A trivial observation, perhaps, but significant nevertheless because it highlights the importance of the survival instinct in all living creatures — sentient, extraterrestrial or otherwise.

Virtually all human societies
have been concerned with
biotechnology, and there is
no reason why alien cultures
on other worlds shouldn't
display similar interests.

Aboriginal medicine men

Indeed, medicine is one of the oldest technologies known to man. Aboriginal peoples who have never seen a wheel or struck a fire guard their lives by employing "medicine men." These specialists in incantation and retaliatory voodoo perform curative rituals to relieve suffering among the sick and the dying, and dole out primitive herbal preparations (some of which work quite well) to alleviate pain. Virtually all human societies have been concerned with biotechnology, and there is no reason why alien cultures on other worlds shouldn't display similar interests.

Participative evolution

Scientists increasingly tend to speak of the concept of "participative evolution," the notion that a race of technically-oriented sentient beings can seize a certain measure of control from Mother Nature and alter their physiology as they wish. With advanced genetic techniques, mankind is learning to control its own biological destiny. It is unreasonable to expect ETs to lag far behind.

Admittedly, the arguments for advanced xenobiotechnology are not compelling.

  • It may be that some alien species have biochemical hereditary mechanisms that are not easily susceptible to intelligent tampering.
  • Other races may inhabit planets poor in the materials necessary in the research and development of artificial bionic devices and mechanical prostheses.
  • Still others may have the native ability to evolve in direct response to the environment by the inheritance of acquired characteristics or by xerography, and thus would view biological technology as irrelevant.
As a general rule, science "evolves"
as a whole. There are few cultures on
record that display grossly disparate
or uneven technical development.
(One notable exception was the
Mayan civilization, which apparently
had some skill in surgical techniques
yet neverdeveloped the simple wheel.)
It’s probably safe to assert that the
survival of planet-evolved beings in
space should be viewed as prima facie
evidence of a developed biotechnology.
Science evolves as a whole

Still, the arguments are persuasive. As a general rule, science "evolves" as a whole. There are few cultures on record that display grossly disparate or uneven technical development. (One notable exception was the Mayan civilization, which apparently had some skill in surgical techniques yet never developed the simple wheel.) On timescales of millennia, the methods of chemistry, physics, mathematics, biology and engineering usually mature at roughly comparable rates. We might expect, therefore, that all Type III galactic cultures-having either sophisticated interstellar transportation or advanced transgalactic communications — most likely will have developed their medical and biological sciences to an equivalent superior level.

Type II cultures

What about Type II stellar cultures? It is certainly possible that early spacefarers might lack advanced biotechnology, but this situation would not seem likely to continue. To remain alive and healthy in the environment of space, a great deal of radiological, physiological, biochemical and ecological information must be available. It’s probably safe to assert that the survival of planet-evolved beings in space should be viewed as prima facie evidence of a developed biotechnology.

Type I cultures

As for Type I planetary civilizations, the arguments for advanced biotechnology are still valid but become a bit more complicated. Random short-term factors may enter the picture. Some sciences may lag far behind others for peculiar environmental or cultural reasons. The very philosophy of participative evolution itself may be rejected as unholy, inelegant, unnatural or unwise by some planetbound alien societies. But if we consider only those races among whom heredity proceeds genetically and whose population swells exponentially (as with humans), a strong case for high xenobiotechnology may be made.

Genetic load

The virtually inevitable development of some kind of medical science, coupled with the gradual loss of challenging physical frontiers (due to the inherent finiteness of planetary surfaces), may eventually lead to a weakening of the gene pool of the population. Genetic load — the slow accumulation of maladaptive genes among members of tool-using, protective species — will become acute within a few millennia following the introduction of medicine and the disappearance of frontiers (as the planet fills to capacity).

Genetic load


■ The slow accumulation of maladaptive genes
   among members of tool-using, protective species.

■ Will become acute within a few millennia following
   the introduction of medicine and the disappearance
   of frontiers (as the planet fills to capacity).

Symptoms of genetic disability may be masked by quick medical fixes, but congenital defectives will no longer be culled by the rigors of frontier existence. Eventually, the population as a whole will become so dysfunctional that only four alternatives will remain:

  1. Do nothing, become more dysfunctional, and ultimately become extinct as a species.
  2. Eliminate a root cause of genetic load by rejecting all medical science. Nature can then cull defectives and maintain a healthy, vigorous gene pool.
  3. Eliminate a root cause of genetic load by expanding physical frontiers and becoming spacefaring. Although stay-at-home defectives won’t be culled, the rigors of space living will ensure a staunch pioneer gene pool.
  4. Eliminate genetic load by taking direct control of biological evolution. Gene defects are remedied prenatally, so that every newborn is a perfect (but nonstandardized) genetic specimen.
  • Societies which choose (1) aren’t around any longer.
  • Those which choose (3) go on to become Type II cultures, whom we have argued will have biotechnology just as those who choose course (4).
  • Alternative (2) is unlikely, both be cause the fruits of medical science are sweet and addictive, and because such a solution will reduce the population-carrying capacity of the planet by several orders of magnitude — which means death on a massive scale.
Genetic and cybernetic participative evolution

Participative evolution among any sentient race will progress primarily along two major fronts:
the genetic and the cybernetic.

  • Biological organisms may be improved either by genetic engineering (repairing, replacing, or augmenting body organs with other new ones).
  • Or by cybernetic or bionic engineering (exchanging living parts for mechanical ones).

In either case, the extraterrestrial sentients become masters of their own heredity.

16.1.0 Bioneering
Bioneering
r-w emerson


Manipulating the executive
molecules of life … should
be more or less universal

Biological engineering — "bioneering" for short — is the technology of genetic engineering. While the nucleic acids represent the blueprints for all Earthly organisms, the biochemical specifics may vary from world to world. Still, the general principle of manipulating the executive molecules of life — whatever they are — should be more or less universal.

Xenobiologists today believe that it will soon be possible to: splice, repair, recombine, synthesize, and transplant specific terrestrial genes and chromosomal patterns between individuals and even between species. What humanity will probably achieve in the coming century may already be well-known to countless advanced extraterrestrial bioneers as well.

16.1.1 Intelligence Amplification

It is impossible to rule out the possibility
of genetically amplified, bioneered aliens,
possessing memory, mental acuity and
speed of thought comparable to some of the
finest computers available on Earth today.
Arithmetic wizards

People have long been astounded by the feats of so-called "human calculating machines." An 18th-century Englishman named Jedediah Buxton reputedly could multiply three 6-digit numbers in his head almost instantly, but his mind was otherwise dull and he remained a day laborer all his life. Zerah Colburn, a rather shy Vermontian born in 1804, attracted even more attention as a child by solving involved mathematical problems. Taken to London at the age of eight, he gave math professors instantaneous answers to such questions as raising 8 to the 16th power and extracting the cube root of 268,336,125. Another mental marvel, Johann Martin Dase, was born in Hamburg, Germany in 1824. Dase once correctly multiplied together two 100-digit numbers in his head in only nine minutes.

Jedediah Buxton
  ■ Could multiply three 6-digit numbers
      in his head almost instantly


Zerah Colburn, at the age of eight
  ■ Could raise 8 to the 16th power
  ■ Extract the cube root of 268,336,125


Johann Martin Dase
  ■ Multiplied together two 100-digit numbers
      in his head in only nine minutes


Elijah of Vilna, during his lifetime
read more than two thousand treatises
  ■ He could recall any sentence on any page
      in any book at will, without error
  ■ Was unable to forget anything he’d read
      (an ability he regarded as a curse)
  ■ His memory represented a storage capacity
      of five billion bits of information (5GB)

Since there really was nothing unusual about the upbringing of any of these individuals, the simplest explanation is that their abilities were congenital in origin. Through some odd shuffling of the genetic deck, some gene or sequence of genes produced a brain of incredible calculational capability rivaling at least that of early-generation electronic computers. If ETs encouraged the spread of some similar hereditary pattern throughout their own gene pools, their entire population could become a race of arithmetic wizards.

Total-recall

Other aspects of intelligence similarly may be upgraded. One well-known case of fantastic memory was Elijah of Vilna, a Lithuanian rabbi, who during his lifetime read more than two thousand treatises. He could recall any sentence on any page in any book at will, without error, and was unable to forget anything he’d read — an ability the rabbi regarded as a curse. His memory represented a storage capacity of at least five billion bits of information — again, a capacity comparable to the large magnetic disk memory units used in modern computers.

It is entirely possible that aliens, by judiciously selecting specific constellations of genes, could arrange to give themselves and their offspring total-recall eidetic memories, fast arithmetic ability, and a host of other genius-level mental qualities.

Memory molecules

In a series of experiments, Dr. Allen L. Jacobson of the University of California showed that RNA functions as a carrier of memory in the mammalian brain. Jacobson taught rats and hamsters to retreat into a feeding box at the flash of a light or the sound of a click. The conditioned animals were sacrificed and the RNA carefully extracted from their brains. This material was then injected into untrained animals of the same species, who subsequently proved far easier to train than their predecessors. One unexpected finding was that the transfer of learning worked cross-species: Untrained rats benefited from injections of trained-hamster RNA.

Injected directly into the bloodstream,
synthetic viruses consisting of nothing more
than a central core of nucleic acid
(commonly RNA) surrounded by a sheath
of protein could be used to "infect" a brain
with knowledge.
Much basic knowledge — the ability to walk,
to speak in many tongues, to swim and dive,
to pilot a spacecraft, to perform intricate
mathematical calculations using established
techniques, to play a piano — could be
incorporated directly into the nucleus of the
fertilized egg so that the organism would
possess all these abilities without ever
having to learn them.

If these results can be confirmed, the implications of such "memory molecules" are staggering. Injected directly into the bloodstream, synthetic viruses consisting of nothing more than a central core of nucleic acid (commonly RNA) surrounded by a sheath of protein could be used to "infect" a brain with knowledge. Remarks one writer:

We would be able to learn French, or algebra, or anything else whose code we knew, by injection. One can imagine education by mass inoculation, or the use of bacteriological warfare techniques for beneficent purposes by spraying entire populations with "good" viruses. The teaching of many subjects would become obsolete).1860

Born smart

Drs. Alexandre Monnier and Paul Laget, French geneticists, have suggested that these coded forms of knowledge be written directly onto the original genetic specifications. Like the social insects, who carry a plethora of pre-programmed knowledge in their genes, humans of the future or extraterrestrials of other planets might be able to arrange to be "born smart." Each infant could carry the genes to manufacture RNA information equivalent to several university doctoral degrees. Much basic knowledge — the ability to walk, to speak in many tongues, to swim and dive, to pilot a spacecraft, to perform intricate mathematical calculations using established techniques, to play a piano — could be incorporated directly into the nucleus of the fertilized egg so that the organism would possess all these abilities without ever having to learn them.

The evolution of physically larger brains by deliberate breeding and selective gene transplantation is another practical option for ETs seeking intelligence amplification. "Is it very rash," asks Dr. Jean Rostand, "to imagine that it would be possible to increase the number of brain cells?" His answer:

A young [human] embryo has already in the cerebral cortex the nine billion pyramidal cells which will condition its mental activity during the whole of its life. This number, which is reached by geometric progression or simple doubling, after 33 divisions of each cell (2, 4, 8, 16, 32, and so on), could in turn be doubled if we succeeded in causing just one more division — the 34th.2645

The supercranial fetus could be produced
in an artificial womb. Since the opening
could be made as large as required,
the impossible-birth consideration
is largely irrelevant.
Artificial womb

Many neurologists remain skeptical of such suggestions, claiming that normal birth would be quite impossible with a head so large. According to Dr. H. Chandler Elliot:

The man of the future was depicted by early fantasy writers with a huge head to house a superbrain; but this picture is discarded by modern sophisticated science fiction as naive and implausible, even for inhabitants of other worlds.90

But as Rostand has pointed out, the supercranial fetus could be produced in an artificial womb. Since the opening could be made as large as required, the impossible-birth consideration is largely irrelevant.

It is impossible to rule out the possibility of genetically amplified, bioneered aliens, possessing memory, mental acuity and speed of thought comparable to some of the finest computers available on Earth today.

16.1.2 Genetic Surgery

The degree of genetic individuality may be
so great among extraterrestrial bioneering
races that each organism might represent
his own distinct and unique "species."
The methods of genetic surgery will
often require the deft insertion of new
genes into the nuclei of malfunctioning
cells. This is called a "gene transplant,"
Each cell contains all of the organism’s
genetic information … If the expression
of these hidden parts of the gene package
can be unblocked, new limbs and organs
could be grown by stimulating the correct
genome sequences at the right locations.
Nerves might be regenerated, eyeballs
repaired, arms / legs regrown from scratch.

"Genetic surgery" is a term used to describe the manipulation of DNA and RNA — the executive molecules of terrestrial life — for specific purposes. Many scientists believe that in the near future human biotechnology will be able to "delete undesirable genes, insert others, and mechanically or chemically transform others."92

Gene transplant

The methods of genetic surgery will often require the deft insertion of new genes into the nuclei of malfunctioning cells. This is called a "gene transplant," a technique already proven by tests involving human subjects. In one early experiment conducted by Carl Merril, Mark Grier, and John Petriccione at the National Institutes of Health in Bethesda, Maryland, specially prepared virus were used to carry DNA into cultured cells taken from people suffering from galactosemia (an enzyme-deficiency disease). After the viruses and the human cells were mixed together in solution and warmed to normal body temperature, the researchers found that the cells had absorbed a gene which had been placed in the virus that was capable of repairing the deficiency. The transplant complete, the cells began to manufacture the previously deficient enzyme in adequate quantities.

In 1970, Dr. Stanfield Rogers, a medical geneticist at the Oak Ridge National Laboratory in Tennessee, performed one of the first experiments on human subjects. A group of children had a rather rare genetic disease called Argininemia, a congenital disability to produce an important enzyme called arginase because of defects in the chromosomal DNA. Rogers selected a microorganism called Shope virus which, while harmless to humans, causes the cells it invades to produce an excess of arginase. A few months after the young children were injected with Shope virus, their bodies began producing the needed enzyme — proof that the viral treatment was beginning to work. The foreign arginase-producing genes had been transplanted into some of the children’s cells.2365

Transplantation biotechnology

Genetic surgery and transplantation biotechnology may give ETs the ability to regenerate lost limbs or damaged organs. Each cell contains all of the organism’s genetic information, but most of it is suppressed because of specialization as a nerve cell, liver cell, or brain cell. If the expression of these hidden parts of the gene package can be unblocked, new limbs and organs could be grown by stimulating the correct genome sequences at the right locations. Nerves might be regenerated, eyeballs repaired, arms and legs regrown from scratch.

Unique species

Similar techniques could possible minor modifications in physical appearance — such as skin or hair color change — or major modifications in body form such as extra arms, fingers, or special organs. The degree of genetic individuality may be so great among extraterrestrial bioneering races that each organism might represent his own distinct and unique "species."

16.1.3 Genetic Hybrids and Synthetic Genes

Much as man learned long ago to domesticate
and cultivate the lifeforms of his world,
sentient bioneering races will learn to exploit
the gene as well for their own purposes.
Genetic hybrid organism … The methodology,
is simple and can probably be done as a
high school science experiment.
It appears quite possible to create hybridized
plants and animals, beings not found in nature.
It would be, as one researcher jokingly put it,
"like crossing an orange with a duck."

Where will participative evolution lead? Eventually ETs, as man, will no longer be satisfied merely with correcting errors and improving upon the old models. Rather, they will have the urge to go nature one better, to create new synthetic organisms for specialized purposes.

Recombinant DNA

Dr. Paul Berg of Stanford University (one of the first scientists to perform "recombinant DNA" experiments) in 1973 mixed together fragments of a bacterial "plasmid" (tiny circlets of DNA imparting resistance to antibiotics) with genes from a virus that produces cancerous virus in monkeys, in a single test tube. These combination virus-plasmids were then allowed to invade normal E. coli bacteria, which soon began churning out viral protein. Using simple gene splicing, Dr. Berg had created a "genetic hybrid" organism — a cross between a cancer-producing virus and a bacterium — which had never before existed in nature. The methodology, says Berg, "is simple and can probably be done as a high school science experiment."2365

Since 1973, scientists have used plasmids to introduce mouse and frog DNA into bacterial cells. It appears quite possible to create hybridized plants and animals, beings not found in nature.* It would be, as one participant at the 1976 Asilomar Conference on recombinant research jokingly put it, "like crossing an orange with a duck."

Much as man learned long ago to domesticate and cultivate the lifeforms of his world, sentient bioneering races will learn to exploit the gene as well for their own purposes.

Hybridized cells can be harvested
for hormones much as a farmer
reaps a field of wheat.
Genetic cultivation

As regards most biochemical substances, mankind is still in the "food gathering" stage. Many needed hormones, such as insulin, must be laboriously collected from scores of individual animal organs. But this situation has begun to change in the last few years. Scientists have succeeded in transplanting a gene for rat insulin into bacterial cells which is reproduced when the cells divide, and it will soon be possible to switch the gene on as well. By cultivating insulin-making DNA, keeping it supplied with the raw materials and energy it needs, hybridized cells can be harvested for hormones much as a farmer reaps a field of wheat.

Hormone factory

Along these lines, Drs. Herbert Boyer, Arthur Riggs, and Wylie Vale spliced the gene for somatostatin into the DNA of E. coli bacteria. Somatostatin is a hormone in the brains of mammals that inhibits the secretion of pituitary growth hormone. The hybridized bacteria multiplied and began producing somatostatin in copious quantities. Before, nearly half a million sheep brains were needed to isolate 5 milligrams of somatostatin. Using the E. coli "hormone factory," scientists required only 8 liters of bacterial culture to obtain the same amount.

Synthetic genes

The key to genetic cultivation is the synthetic gene — artificial nucleic acid sequences that have never occurred in nature. The first total synthesis of a complete gene starting from scratch was first accomplished by Nobelist Har Gobind Khorana and his team at MIT. The experiment involved the re-creation of a "tyrosine transfer RNA gene" found in E. coli which is 207 nucleotide base pairs in length. While it took the MIT group nearly a decade to do it, they are confident that genes as complex as those of humans (1000-3000 nucleotide base pairs long) will be amenable to synthesis in the next fifty years.2646 It is then a relatively simple step to the production of "unnatural" genes.

Such animal slaves should be
herbivorous because carnivores are
much too expensive to feed and
might take a fancy to their riders.
Genetically augmented domesticated beasts

With the ability to create artificial genomes with specific desired characteristics, alien bioneers can better exploit the whole animal kingdom. Domesticated beasts with augmented intelligence and specially modified limbs and organs might function as excellent animal servants. Genetically altered horses might be used as intelligent, self-steering, self-feeding, self-cleaning, self-reproducing personal transport vehicles. Arthur C. Clarke points out that something resembling a compact elephant might be preferable in this regard, since it is the only quadruped with sufficient dexterity to carry out delicate handling operations while remaining a quadruped.55 Such animal slaves should be herbivorous because "carnivores are much too expensive to feed and might take a fancy to their riders."

Lesser lifeforms may be pressed into service by ETs. Genetically upgraded birds could be used as aerial messengers and scouts, and would be trained to speak some simple language. Traitor fish could be developed to steer schools of their unsuspecting fellows into the waiting nets of fishermen. Vicious insects, giant crustaceans and monstrous mollusks could be bred as offensive weapons of tactical warfare.

GM mining organisms

Freeman J. Dyson of the Institute for Advanced Study at Princeton University has suggested the possibility of exotic, genetically-modified artificial mining organisms, trolling the seas of planets for valuable minerals and metals. Says Dyson:

Oysters might extract gold from seawater and secrete golden pearls. A less poetic but more practical possibility is the artificial coral that builds a reef rich in copper or magnesium. Other mining organisms would burrow like earthworms into mud and clay, concentrating in their bodies the ores of aluminum or tin or iron, and excreting the ores in some manner convenient for human harvesting.27

The extraterrestrial bioneers may themselves
be the subjects of genetic modification.
Instead of creating expensive, cumbersome
artificial environments to sustain their lives
after planetfall, ETs may decide to undergo
a change in basic physical form enabling
them to survive the natural conditions
encountered on each new world.

At least one mining company already uses bacteria to help recover copper metal from a variety of low-grade ores.88

ETs as subjects of genetic modification

The extraterrestrial bioneers may themselves be the subjects of genetic modification. Instead of creating expensive, cumbersome artificial environments to sustain their lives after planetfall, ETs may decide to undergo a change in basic physical form enabling them to survive the natural conditions encountered on each new world. Conforming to the alien environment should facilitate both exploration and first contact, should it occur, with sentient natives.2651

Advanced xenobiotechnology will allow extraterrestrial astronauts to decide which form was most convenient. Should they wish to explore and inhabit Jupiter for a period of time, for example, they could infect themselves with a carefully tailored virus containing modified genetic material. Cells in their bodies would be taken over by the intruders. Some would metamorphose into, say, jovian "gasbag beasts," while the rest would simply die away and be sloughed off like molted skin. Later, the gasbag genes might be replaced with new ones coded to produce a large-chested surface creature capable of breathing the 0.1% oxygen atmosphere of Mars. Finally, their survey completed, the ETs would be returned to their normal spacefaring designs using yet another application of a different transmutation virus — perhaps a small, agile humanoid form with a dexterous prehensile tail and a high tolerance for conditions of low gravity and sudden atmospheric decompressions.

When first contact with extraterrestrials occurs, we won’t know if the aliens are truly as they appear or rather inhabit genetically doctored bodies. Perhaps those tan-skinned humanoids we just shook hands with are really a race of chlorine breathers with twelve greasy tentacles and porcupine-bristled fur.


Plantimal

* In 1976, researchers at Florida Atlantic University at Boca Baton created the first "interkingdom protoplast" which they call the "plantimal."1617 Joined were a human cell nucleus and a tobacco cell nucleus, and, in another experiment, a human nucleus and a carrot nucleus. Extraterrestrial bioneers may have developed photosynthetic meatlike "blobs" to serve as protein livestock, shapeless amorphs which convert sunlight directly into edible meaty material. Autotrophic animals such as "plant men" similarly may be possible.

16.1.4 Ectogenesis and Cloning

Instead of keeping adult ET travelers in suspended
animation for hundreds of years in transit
between stars, compact frozen embryos could be
dispatched to the target solar systems. Upon
arrival, these ectogenetic astronauts would be
fertilized and carried to term in an artificial womb.

At birth, cybernetic devices or RNA memory
molecules could be used to teach the infant about
their culture, their science, and their mission.
The starship would then enter orbit around the new
world and finally land, the now-adult alien
colonists emerging to begin life on foreign soil.
Test tube pregnancy

Ectogenesis is the process of "test tube pregnancy" as exemplified by Aldous Huxley’s science fiction classic Brave New World.  If an artificial placenta can be designed, complete artificial development of an entire human being will be possible starting only with sperm and egg. As long ago as 1959, a plastic womb designed by Italian surgeon and medical experimentalist Daniele Petrucci carried developing human embryos for nearly two full months. There are recent reports that the first human test tube birth has already taken place,2871 although these are discounted by most reputable scientists.2872

Aside from using ectogenetic techniques to control birth rates or maintain rigid biological castes, aliens might find test tube birth an ideal solution to the problem of interstellar colonization. Instead of keeping adult ET travelers in suspended animation for hundreds of years in transit between stars, compact frozen embryos could be dispatched to the target solar systems. Upon arrival, these ectogenetic astronauts would be fertilized and carried to term in an artificial womb. At birth, cybernetic devices or RNA memory molecules could be used to teach the infants about their culture, their science, and their mission. The starship would then enter orbit around the new world and finally land, the now-adult alien colonists emerging to begin life on foreign soil.

Cloning

Cloning is a related biotechnology that ETs will probably have. It’s a form of genetic engineering by which many exact duplicates of the original organism may be produced. Except for blood corpuscles, every cell in the mammalian body has identical and complete sets of genes which uniquely specify the entire organism. The nucleus from a human skin cell transplanted into an ovum and carried to term ectogenetically should produce an exact twin of the original donor. In 1969, Dr. John B. Gurdon at Oxford University succeeded in creating countless cloned frogs by transplanting genes from adult frog cells into the nuclei of frogs’ eggs.

Cryobiology

Aliens will find many interesting uses for cloning. According to technologist Robert W. Prehoda, a combination of cloning and cryobiology (low-temperature preservation) could permit useful plants and animals to be conveniently transported with interstellar colonizers to make it easier to quickly populate barren planets with the flora and fauna of home.67 Cloning may also allow alien plants and animals to be reproduced in great numbers back on the home world, after interstellar expeditions across the Galaxy return with frozen cell samples of exotic foreign lifeforms. Extraterrestrial bioneers may also clone duplicates of themselves as successors in political office,1947 as standardized military units, or as nonsentient living warehouses for biological spare body parts for organ transplantation operations.

16.2 Immortality
16.2.0 Immortality
t-j bass
The basic survival instinct must be very deeply
ingrained in many alien races. This, in concert
with a sophisticated biotechnology, provides both
motive and opportunity for the development of
immortality among extraterrestrial civilizations.


Recalling Medawar’s assertion about human nature cited earlier, can we be as certain that aliens too "would rather be alive than dead"?

Genetic sentience

Maybe not. Consider the alternative forms of sentience discussed in Chapter 14. Beings with genetic sentience — "intelligent ants" — may harbor no desire for personal immortality whatsoever. Since they aren’t aware of their individual selves, they could never sympathize with Ionesco’s very human lament: "Why was I born if it wasn’t forever?" Since the society of these creatures would be virtually immortal, genetic-sentient ETs may have no use for the concept of (effectively) perpetual personal existence.

Communal sentience

Similarly, beings with communal sentience (visceral social awareness) may be able to take solace in the comparatively eternal character of society. It may be that the appetite for immortality displayed by many humans is a hunger unique to brain-sentient species. Only among these races must the individual deal with personal death in the absence of any strongly-felt, well-internalized and supportive societal framework.

Of course, even among brain-sentient extraterrestrial species there may be cultural, psychological, or biological reasons why the drive for immortality might be suppressed. Yet the basic survival instinct must be very deeply ingrained in many alien races. This, in concert with a sophisticated biotechnology, provides both motive and opportunity for the development of immortality among extraterrestrial civilizations.

16.2.1 Xenogerontology
Genetically determined programs

Species survival requires a large enough
quantity of individuals in any given generation
to ensure that a significant number of them
will be the beneficiaries of chance mutations
that can be passed along, and a short enough
lifespan to permit the necessary turnover.


According to modern gerontologists, then, aging
is an absolutely fail-safe killing mechanism
without which the species would not survive.

Gerontology is the science of physiological aging and death. Modern researchers have concluded that while no single cause of aging exists, it may soon be possible to sharply reduce or eliminate this process in many Earthly animals — including man. The prospect of such great advancement in human biotechnology raises the presumption that alien gerontologists — xenogerontologists — can do at least as well.

Death from old age is no more "natural" or inevitable than smallpox or plague. As the twice Nobel laureate Dr. Linus Pauling asserted more than twenty years ago:

Death is unnatural. Theoretically, man is quite immortal. His body tissues replace themselves. He is a self-repairing machine. And yet, he gets old and dies, and the reasons for this are still a mystery.2647

To paraphrase the venerable Seneca: Old age is a curable disease.

Clocks of aging

The general consensus among gerontologists today is that there exist within humans identifiable "clocks of aging." These clocks are genetically determined programs which dictate when and how fast we shall age and die. Since such mechanisms appear to be rather common throughout the entire animal kingdom, there is good reason to suspect that ETs should possess something functionally similar. While the mystery of aging has not yet been solved, a tripartite theoretical model with three primary "clocks" has begun to emerge.

First clock: Wear and tear

The first of these is rather simple: Wear and tear. Medawar, one of the earliest scientists to link genetics with aging, has called this the "broken test tube" theory. Say that we start off with 1000 brand new test tubes in a chemical laboratory. Over time, the number of "survivors" would steadily dwindle. Some tubes with factory flaws (birth defects?) would be thrown out first (die?), while others would break from chance accident or hard usage after a number of years. Eventually the entire population of test tubes will have broken in this manner, and we then may plot a "survival curve" of aging and death for the glassware entities. The analogy to the mortality of living beings is inescapable: Wear and tear does us in.

The Hayflick Factor: Lifespan and the Number of Cell Divisions

Table 16.1 The Hayflick Factor:

Lifespan and the Number of Cell Divisions

table 16 1 hayflick factor 400

The second clock of aging is called the Hayflick Factor after UCSF researcher Dr. Leonard Hayflick. In 1961, he discovered that young human cells growing in a culture medium could divide only a limited number of times (roughly 50 generations) before all their descendents aged and died. Cells taken from adults divided even fewer times (about 20) before death ensued.

Hayflick then compared the growth cycles of human cells to those taken from other animals. Not surprisingly, tissues taken from nonhuman creatures differed markedly (between species) as to the total number of generations they could produce before dying. It was also found, however, that animals with longer lifespans also had the longest-lived cells. (See Table 16.1.) Hayflick concluded that cell death in all organisms was an expression of aging at the microscopic level. Aging thus appeared to be a built-in genetic limitation to cellular regeneration and growth.

In the last two decades, Hayflick’s work has
been largely verified. Studies of identical twins
— who, like clones, have identical DNA — show
that both individuals generally have about
the same lifespan. (This is to be expected if
genes control longevity as Hayflick suggests.)

In the last two decades, Hayflick’s work has been largely verified. Studies of identical twins — who, like clones, have identical DNA — show that both individuals generally have about the same lifespan. (This is to be expected if genes control longevity as Hayflick suggests.) In another series of experiments, a number of cultured human cells of various "ages" were placed in cold hibernation at liquid nitrogen temperatures. These were then thawed out, a few at a time, over a period of ten years. Each cell "remembered" its correct "age" and proceeded to divide up to the normal allotment of 50 generations, at which point death set in as usual. In yet another study, nuclei from young cells were transplanted into the protoplasm of old cells. Cells which had already doubled, say, 37 times, which were renucleated with a nucleus from a young cell that had passed through only 10 generations, went on to divide for about 40 more cycles before old age set in.

On the basis of the normal 50 divisions found in human cultured cells, Hayflick calculated that the normal lifespan of man should be about 110-120 years. But we know that only a negligible fraction of the human race ever attains such advanced age. This brings us to the last factor in the tripartite model of aging.

Third factor: Hormonal

After a detailed study of autopsy data and death
records, that most people die because of
a failure of one of the two major body systems:
The cardiovascular or the immune systems.

Dr. W. Donner Denckla, a medical researcher at the Roche Institute of Molecular Biology, believes that the third clock of aging is hormonal in nature and resides somewhere in the brain — most probably in the human endocrine glands. Denckla found, after a detailed study of autopsy data and death records, that most people die because of a failure of one of the two major body systems: The cardiovascular or the immune systems. Death occurs in the former instance from heart stoppage or from an inability of the blood vessels to deliver oxygen and nutrients to vital organs, and in the latter instance from a failure of the body’s immune system to ward off an attack of invading microorganisms.

The thyroid gland, Denckla believes, may be of central importance because its product — thyroxine — appears to be the master rate-controlling hormone. When humans age, they don’t lose the ability to produce thyroxine. Rather, they lose the ability to utilize whatever quantities of the hormone are available.

Death hormone

Denckla suspects that the pituitary may release some kind of blocking hormone — which he calls the "death hormone" — that prevents cells from using thyroxine. The diminishing utility of the vital secretion in later life could cause a number of critical imbalances, increased destructive oxidation, chromosomal mutations and heart tissue dysfunction.

Incompetent lymphocytes

Another endocrine gland — the thymus — has been implicated in the process of human aging. The thymus is a soft, flattened organ just behind the breast bone in man. Older medical texts say that the function of the gland is unknown, but many modern specialists link it to the production of "T cells" (a variety of lymphocyte or "white cells") under the direction of the pituitary and the hypothalamus.

Lymphocytes, our "white cells,"
become increasingly incompetent.

They fail to rid the body of hostile
pathogens and mistakenly attack
the body’s own cells as if they
were foreign invaders.

As a result, older organisms are
vastly more susceptible to a wide
range of potentially lethal diseases.

During life, the thymus changes dramatically in size. At birth it weighs about 12 grams. At puberty it reaches its maximum at 37 grams. Thereafter, it shrinks rapidly until by the age of 40-50 years it has all but disappeared in many people. By age 60 it weighs at most a paltry 6 grams.

According to Dr. Allan Goldstein of the University of Texas Medical Branch, Galveston, the level of thymosin — the secretion of the thymus gland — falls off with age in direct proportion to the diminishing size of the organ. As the concentrations of thymosin drop, the failure rate of the human immune system rises markedly. Lymphocytes, our "white cells," become increasingly incompetent. They fail to rid the body of hostile pathogens and mistakenly attack the body’s own cells as if they were foreign invaders. As a result, older organisms are vastly more susceptible to a wide range of potentially lethal diseases.

To test his theory, Goldstein has injected thymosin into children afflicted with severe immune-deficiency diseases. The revitalization of the youngsters’ immune systems was dramatic, but more verification is necessary. The next step will be to try to revitalize aging immune systems in adult humans using similar therapy. If these experiments succeed, immune failure as a cause of death could virtually be eliminated.

Three clocks of aging

Figure 16.1 Human Current and Future Mortality

Figure 16.1 Human Current (left) and Future (right) Mortality
figure 16 1 540
Figure 16.1 Human Current Mortality
figure 16 1 human current mortality 540
Figure 16.1 Human Future Mortality
figure 16 1 human future mortality 540px

STAGE 1 DEATHS: Hormonal imbalance causes failure of cardiovascular G immune systems.

STAGE 2 DEATHS: (Hormone imbalances corrected.)
                          Genetic cellular aging program shuts cells off automatically.

STAGE 3 DEATHS: (Genetic cellular aging program erased.)
                          Accidents and general irreversible deterioration.

Regardless of the exact mechanisms of hormonal control, argues Denckla, the control is there. And it would appear to have great survival value. So far as we know, Earthly species evolve naturally only by mutation, a fairly slow process. To speed it up, more parents must be cycled through the system. The faster the turnover rate in the reproducing population, the more variability will be available quickly from the gene pool. Mortality of individuals thus has selective value because, in the words of one writer, "species survival requires a large enough quantity of individuals in any given generation to ensure that a significant number of them will be the beneficiaries of chance mutations that can be passed along, and a short enough lifespan to permit the necessary turnover."2137

According to modern gerontologists, then, aging is "an absolutely fail-safe killing mechanism without which the species would not survive." Under the general tripartite theory (Figure 16.1), three clocks of aging are simultaneously ticking against us. If one stage of the death process is escaped, others remain:

  • Stage 1 — Denckla/Goldstein hormonal imbalances occur which cause the cardiovascular and immune systems ultimately to fail. This is the body’s primary self-destruct mechanism. Typical life expectancy: 30-80 years.
  • Stage 2 — The Hayflick cellular aging program causes body cells to cease dividing after a fixed number of generations. It is designed to set a second limit in case the Stage 1 hormonal malfunction is ineffective. This is the body’s secondary self-destruct mechanism. Typical life expectancy: 110-120 years.
While the tripartite aging model may turn out to be correct
for mammalian life on Earth, this is no guarantee that
beings of other worlds must be designed in the same way.

Still, the basic evolutionary concept of the survival value
of death for naturally evolving species should be as valid
in alien ecologies as it is on this planet.

There is no reason to suspect that extraterrestrial aging
mechanisms will be any more or less complicated than our own.
  • Stage 3 — Medawar’s "broken test tube" wear and tear on body structures. Irreversible genetic deterioration or severe accidental trauma eventually cause senescence and death. This is the body’s last line of defense against immortality, a tertiary backup system. Typical life expectancy: ~1000 years.

While the tripartite aging model may turn out to be correct for mammalian life on Earth, this is no guarantee that beings of other worlds must be designed in the same way. Still, the basic evolutionary concept of the survival value of death for naturally evolving species should be as valid in alien ecologies as it is on this planet. There is no reason to suspect that extraterrestrial aging mechanisms will be any more or less complicated than our own.

16.2.2 The Limits of Immortality

The "brain barrier" problem

Three solutions


  • First solution: Genetic engineering
  • Each individual starts out with a larger brain
  • Second solution: Regeneration
  • Brain cells regenerate as others die
  • Third solution: Slow attrition
  • Prevent neural cells from dying at all or
  • Significantly slow the rate of attrition

Brain cells do not reproduce and cannot replace themselves once destroyed. Each human possesses ten billion irreplaceable neurons; when some are lost due to concussion, consumption of alcohol or tobacco, or from natural causes, our brains are permanently diminished.

Dr. Harold Brody of the State University of New York at Buffalo attempted to measure the rate of natural attrition of brain cells. While losses range from none at all to very many in various parts of the organ, the approximate brainwide average runs about 100,000 neurons lost per day. At this rate, Brody calculates, the organ should entirely decay away in a period of about 250-350 years.2648 Whether cell loss would actually continue to the vanishing point or would taper off asymptotically is unknown at present.

Genetic engineering

There are at least three solutions to the so-called "brain barrier" problem. First, genetic engineering could permit each individual to start out with a larger brain. If the ETs have 100 billion neurons — ten times more than we — and the same neural attrition rate, senility might not set in for thousands, instead of hundreds, of years. The full millenium of Stage 3 aging would then become available to the aliens.

Regeneration / reproduction

A second solution is to cause brain cells to regenerate and reproduce them selves as others died. If neuron division could be exactly balanced against cell losses, the brain would remain the same size and theoretically could go on forever. This again will only be found among extraterrestrial races capable of advanced bioneering, since there is no natural selective value in developing complex brain regeneration mechanisms which aid survival only if the organism manages to pass the primary and secondary self-destruct systems of the body. What if aliens did have divisible brain cells? In his book The Immortality Factor, Osborn Segerberg, Jr. writes:

What would be the fun of attaining
great longevity if the lucky winner
couldn't remember what had gone before?

[Brain cells] store our memories, experiences, knowledge and learning as well as operate voluntary and autonomic nervous systems. New brain and nerve cells presumably would "forget" what their predecessors knew. If the [being] survived the neurological havoc, he might not be able to retain his identity. He would forever be turning into someone else.69

Or, as another writer puts it: "What would be the fun of attaining great longevity if the lucky winner couldn't remember what had gone before?"2137

Of course, the counterargument goes like this: We know we lose 100,000 neurons every day. If this causes personality change from day to day, we certainly do not notice it. Why should the random addition of 100,000 neurons every day wreak any more cerebral havoc than their random subtraction? Brain regeneration may be quite possible, after all.

One recent science fiction story proposes
the development of a sense of precognition
or foreknowledge to enable the creature
to anticipate accidents in the near future
and avoid them.

This accomplished, there should be no
further real limits to immortality, save
boredom or a brain jammed to capacity
with memories like a well-worn palimpsest.

Death would occur only as a matter
of affirmative, intelligent choice.
Slow rate of attrition

A third solution to the brain barrier problem is simply to prevent neural cells from dying at all, or at least to significantly slow the rate of attrition. We don’t know how to do this yet — perhaps more robust and wear-resistant cells could be designed — but alien sentients elsewhere may have already found the answer.

Assuming ETs and earthlings manage to lick the brain barrier problem, then exactly what are the limits to immortality? Saving the organ of sentience doesn’t get us out of the woods yet, because there is still the problem of accidental death associated with Stage 3. Individuals may be hit by a truck, slip in the bathtub, be shot in battle, or die in a plane crash.

Still, the lifespan in Stage 3 may be an order of magnitude greater than in Stage 1 (where humans are now). For example, the death rate in the United States in 1973 was 942 deaths per 100,000 people. The maximum lifespan attainable was about 100 years. If all purely medical deaths were eliminated, leaving only suicide, homicide and accidental causes (fire, drowning, lightning, and other sudden traumas), the death rate would have dropped to 78 cases per 100,000 people. This works out to a maximum attainable lifespan of nearly 1300 years, as shown in Figure 16.1.

Is this the upper limit, then? If accidental causes of death can be eliminated we can get more. But how could this be done? One recent science fiction story proposes the development of a sense of precognition or foreknowledge to enable the creature to anticipate accidents in the near future and avoid them.2650 This accomplished, there should be no further real limits to immortality, save boredom or a brain jammed to capacity with memories like a well-worn palimpsest. Death would occur only as a matter of affirmative, intelligent choice.

16.3 Androids and Cyborgs
16.30 Androids and Cyborgs
robert heinlein


Androids

■ purely biological

Cyborgs

■ part biological

■ part mechanical

Robots

■ purely mechanical

As we have seen, there are few limits to the possible accomplishments of alien biotechnologists. But the biological forms which nature has provided are especially well-adapted to a pretechnological planetary environment. ETs may need to design new forms to accomodate the requirements of a fast-paced industrialized technical society. Genetic manipulation might turn out to be a natural prerequisite to man-machine coupling. For example, gene surgery may permit body proportions to be altered to better fit the dimensions of mechanical systems such as computers and starships.

Sentient extraterrestrials thus may turn to synthetic biological or to bionically-augmented designs which possess the desired characteristics of high reliability, great longevity, and which interface more perfectly with various technological aspects of the environment. There are three general classes of such entities: Androids (purely biological), cyborgs (part biological and part mechanical), and robots (purely mechanical).

16.3.1 Androids and Organleggers

Table 16.2 Human Organ Transplant Biotechnology as of 19762365

table 16 2 human organ transplant biotechnology 400

An android is a living being
that has been created partly
or wholly through processes
other than natural birth.

Exactly what is an android? There seems to be much confusion on this score even among science fiction writers. Some hold that an android is an automaton in human form; others describe it as a robot that can think. Still others require it to be biological, while a few permit both biological and mechanical "androids." Perhaps the most consistent traditional definition is the one offered by Groff Conklin in 1954: "An android is a living being that has been created partly or wholly through processes other than natural birth."1836

The classic biological android was the fictional Frankenstein monster created by the pen of Mary Shelley — a living organism assembled in pieces by men. Under the Conklin definition, clones would probably also be regarded as androids. What of nonhumanoid forms? Arthur C. Clarke has coined the word "biot" (short for "biological robot") to refer to all animal androids, nonhuman beasts created by the hand of sentience. Remarks Freeman J. Dyson of the biot:

I would say that when we learn…
to create intelligence. I think it will
not look like an electronic computer,
but rather more like a living organism.

I would say that when we learn to use these biological techniques ourselves, and to build machines with biological materials, we shall probably be able to create intelligence. I think it will not look like an electronic computer, but rather more like a living organism.1558

Jeremy Bernstein, Professor of Physics at the Stevens Institute of Technology in New Jersey, echoes this sentiment when he states:

The lesson of modern biology is that the distinction between living and nonliving material is almost arbitrary. So it is possible that one would be able to make machines biologically, in test tubes rather than in an electronics factory, and then it will be almost an arbitrary question as to whether one wants to call such objects machines or living animals.1558

One of the patients big toes is
transplanted onto the thumb stump.

"Close up it looks a little strange,"
remarked one writer, "but it does the job."
Organ transplant technology

Terrestrial organ transplant technology has advanced markedly in the 1970s. As shown in Table 16.2, transplants of virtually every major human organ have been attempted with increasing success.* Furthermore, the art of microsurgery — essential fine detail work with tissues and capillaries involved in transplantation — has made fantastic progress. Skilled microsurgeons now suture tiny capillary walls and can reconnect delicate wisps of nerve tissue, working under a microscope with needle and thread smaller than human hair.2882 For more than a decade, Chinese doctors have been replacing severed limbs with great success — arms, legs, feet and fingers. (Since the thumb accounts for 50% of the efficiency of the hand, microsurgeons can salvage it even when it's smashed beyond repair. One of the patients big toes is transplanted onto the thumb stump. "Close up it looks a little strange," remarked one writer, "but it does the job."2652)

Where might replacement organs come from? They could be cloned from the patient’s own cells, but this takes time. Another way would be to store donated or pre-cloned organs "on ice" until needed. Scientists at the Oak Ridge National Laboratory have developed a technique which may soon make it possible to store human organs for a century or more before thawing for use in a transplantation procedure.2653

Bio-emporiums

William Gaylin, President of the Institute of Society, Ethics, and the Life Sciences, has proposed the controversial idea of using living cadavers, which he calls "neomorts," for medical experimentation and salvaging body parts. Neomorts — living, breathing, feeding and excreting organisms — would nevertheless be legally dead because of the cessation of electrical brain activity (brain death). Gaylin suggests that "bio-emporiums" be maintained using the victims of suicides, homicides and other accidents. Neomorts would serve as body part banks. Organs would be preserved in the still-living bodies, and there would be a regular supply of blood since the living corpses "could be drained regularly."2654

Organlegging


■ Black market in illegally-obtained organs

■ Offering disassembled kidnap victims

to the local Organ Bank

Organlegging

Science fiction writer Larry Niven predicts that widespread demand for donor organs might create a new type of crime which he calls "organlegging." As body parts change from a luxury for the few to a necessity for the many, demand will almost certainly outstrip supply. Niven claims that a black market in illegally-obtained organs would spring into existence, offering disassembled kidnap victims to the local Organ Bank at inflated prices.2020 As man becomes more android, will his crimes become more heinous?

Brain transplants

What about brain transplants? About a decade ago, Dr. Robert J. White of the Brain Research Laboratory at Cleveland Metropolitan General Hospital carefully removed the brains of six dogs. Each organ was placed into the cranium of a new canine and connected to its bloodstream. Some animals perished within six hours of the operation, but one survived for two days. During this time, the living transplanted brain produced electrical signals on the electroencephalograph that was monitoring it.1646 Similar experiments have been conducted successfully on monkeys.2656

This will be a most challenging operation
because the neural configurations in the
donor brain, much like the uniqueness of
fingerprints, will display a complicated
pattern that probably won’t match the
connections in the recipient’s cranium.

But to transplant an entire brain and restore it to full capacity, extraterrestrial microsurgeons must be capable of severing and reconnecting countless millions of individual nerve endings in a very brief span of time. This will be a most challenging operation because the neural configurations in the donor brain, much like the uniqueness of fingerprints, will display a complicated pattern that probably won’t match the connections in the recipient’s cranium.

Whole head transplant

If the whole head is transplanted, however, the cranial nerves continue to function normally.2655 For this reason it has been suggested that aliens may prefer to transfer heads rather than brains. Human scientists have already tried this. In 1957 a Russian surgeon named Vladimer Demikov grafted a second head onto the neck of a dog. The two-headed monstrosity survived nearly a week with apparently "normal" functioning. For instance, when exposed to light and sound both heads responded by trying to bark.2365 Aliens may use similar methods to graft old heads onto freshly-cloned headless neomorts.


Penile transplantation

* A review of the medical literature available in 1976 fails to produce a single instance of penile transplantation.1621 However, 13 cases of replantation of the traumatically amputated penis are noted, and 10 cases of penile reconstruction are recorded in which a new penis was fashioned from other neighboring tissues. A major impasse to penile transplantation appears to be donor organ procurement.

16.3.2 The Bionic Alien
Bionics

Bionics describes the science of constructing
artificial systems that resemble or have
characteristics of living systems.

Specifically, the reference is to a device
which mimics some natural function
of the lifeform or improves upon it.

The word "bionics" describes the science of constructing artificial systems that resemble or have characteristics of living systems. Specifically, the reference is to a device which mimics some natural function of the lifeform or improves upon it. The use of artificial parts in man results in a hybrid entity which has been dubbed a cybernetic organism, or "cyborg." The term was originally applied in astronautics, but now is widely used to describe any creature possessing bionic components — a being created by joining living flesh with nonliving devices.

Because of the great potential utility of artificial prosthetic equipment, and because the space environment is far more hostile to biology than to bionics, the extraterrestrial cyborg is a very real possibility. A bionic alien undoubtedly will represent a vast physical improvement over the original biological model.

  • He may have better senses:
    • • telescopic or infrared vision
    • • high frequency and hypersensitive hearing
    • • perception of radar or x-rays
    • • acute smell or taste
  • He may have powerful limbs like Steve Austin of Six Million Dollar Man TV fame.
  • Perhaps the astrocyborg will simply be more flexible and agile than the original — there’s no premium on raw strength in the weightless conditions of space.
  • He may have bionic blood (a special synthetic formulation based on fluorocarbons which is protein-free and thus generates no immune rejection response) and a bionic beatless heart.
Skin could be photosensitive, absorbing
photons and combining them with blood
gases and water directly to produce
valuable carbohydrates — a new twist
on the "autotrophic man" concept.
Autotrophic man

Extraterrestrial cyborgs may possess bionic skin, a tough rubbery silicone material with enormous tensile strength and high resistance to vacuum and radiation. This skin could be photosensitive, absorbing photons and combining them with blood gases and water directly to produce valuable carbohydrates — a new twist on the "autotrophic man" concept. A step in this direction has been taken by Dr. Joseph J. Katz, a chemist at the Argonne National Laboratory. Katz and his research team have constructed what amounts to a "bionic leaf," a contrivance of metal, glass, plastics and chemicals. The device is designed to produce hydrogen, rather than carbohydrates, from sunlight.2698

And bionic aliens may come equipped with advanced abilities that have no direct biological analogue. For instance:

  • ET astronauts could have a "radiation gland" to warn them of rising radiation levels in the vicinity and to automatically inject protective chemicals directly into the bloodsteam.
  • Aliens may have a direct hookup to their pleasure or sleep centers in the brain, to permit them to while away long hours of waiting without succumbing to acute boredom or depression.
  • Other artificial organs may be implanted which provide radio contact with others, or which monitor internal bodily processes for signs of impending stroke or exhaustion. Appropriate stimulants and energizers could be dumped into the bloodstream during emergency situations.
Human bionics technology

The Utah arm … can flex at the elbow,
rotate at the wrist, and manipulate
fingerlike attachments capable of
holding forks, bottles, or pencils.

It is worth taking a brief look at the state of the art in human bionics technology because it's suggestive of just how well aliens may be able to do.

Bionic arm

Take, for example, the bionic arm. One artificial limb called the "Utah arm," developed by Stephen Jacobsen at the University of Utah, can flex at the elbow, rotate at the wrist, and manipulate fingerlike attachments capable of holding forks, bottles, or pencils.2659 The bionic arm is fitted to volunteer amputees and controlled through a computer. Using sensors on the subjects’ arm stump, tiny muscular contractions are interpreted and translated into the delicate motions of the artificial limb. Dr. Frank Clippinger, Jr. at Duke University Medical Center have created a similar device with feedback, to impart a sense of feeling and touch.2692

While Steve Austin’s superstrong attachments are mechanically improbable, much progress has been made toward the goal of a bionic arm which performs better than the original. Dr. Vert Mooney at the Rancho Amigos Hospital in California has built a prototype 3½ kilogram artificial arm with self-contained battery pack and motors. Sensors connected to muscles in the forearm allow the device to respond almost as well as the original. It was first used on Reid Hilton, a 24-year-old karate expert from Santa Ana who lost his right arm in an automobile accident. Hilton was able to perform extremely fine movements such as tying shoelaces, as well as the larger motions required in karate. Amazingly, the bionic arm has a grip strength of nearly 20 kilograms, as compared to only 10 kilograms for the average man.2691

Bionic eye

Another example is the bionic eye. Opthalmologist William Dobelle of the University of Utah, with the cooperation of blind volunteers, has developed a primitive system for artificial sight. In his experiments, a teflon strip with an array of 64 platinum points is inserted between the two hemispheric halves of the brain, in direct contact with the visual cortex. This grid is wired to external TV cameras through a coaxial cable plug mounted in the subject’s skull.

We hope to develop a functional
artificial eye for the blind, consisting
of a small TV camera in a glass eye,
a small computer system perhaps
built into the frame of a pair of
glasses, and an array of electrodes
on the visual cortex.

When electrical stimulation from the lab cameras reaches the patients’ brains, they report seeing flashes of light — called phosphenes — which are about the size of a small coin held at arm’s length. Most are red, yellow or white in color. One subject, blinded by a gunshot wound more than a decade ago, said that they resembled small lights "like a time and temperature sign on a bank, or a scoreboard at a football game."2660 This same man has been trained to read in a phosphene-Braille system with 85% accuracy at a rate of six words per minute.

Says Dobelle of the system currently in use: "Our objective is not normal vision. It is low definition black and white — analogous to the first television pictures sent from the moon by the astronauts. We do not propose to create a reading system. Mobility is more important to the blind than reading." Still, the ultimate objective of the bionic eye project is considerably more ambitious: "We hope to develop a functional artificial eye for the blind, consisting of a small TV camera in a glass eye, a small computer system perhaps built into the frame of a pair of glasses, and an array of electrodes on the visual cortex."2447 Dobelle estimates that the entire system may be on the market in about ten years, and might sell for a few thousand dollars each.2661

The development of artificial
replacements for human body
parts is one of the fastest growing
areas in medical research today.
Spare-parts catalog

The development of artificial replacements for human body parts is one of the fastest growing areas in medical research today. Bionic ears, complete with sound pickup, amplifier, and rechargeable implantable power supply, will be on the market in the early 1980's.2365 Bionic lungs, kidneys, livers and pancreases have been developed with reasonable success. The spare-parts catalog runs into the hundreds, including dentures and artificial jaws, skull plates, bionic joints and bones, orthopedic pins and shanks and spinal disks, bionic tracheae, larynxes, sphincters, tendons, ligaments and muscles.*


Bionic erections

* Artificial penises and bionic erections are now available, although at considerable cost. Developed as a treatment for physical impotence, the device is made up of two collapsible silicone rubber cylinders placed inside the corpus cave nosum of the male organ. Upon squeezing a tiny pump tucked away behind the scrotum, hydraulic fluid is transferred from an implanted spherical reservoir to the cylinders in the penis, causing the member to become erect.349 This can be maintained for an indefinite period of time, and permits full sensitivity and normal ejaculation. Says neurologist William Bradley, one of the proud developers of the "bionic penis" at the Baylor College of Medicine in Houston, Texas:
"It isn’t like a real erection — it is a real erection. Enlargement, growth in diameter… it's great!"2365

Brain/machine interface

Thinking cap

Figure 16.2 Practical Electronic Telepathy?2699

figure 16 2 practical electronic telepathy

Click for caption

Wearing the latest in this fall’s, scientific hat fashions is Tom Santoro, a researcher at the California Institute of Technology.
Arrays of 30 to 50 scalp electrodes in the hat are designed to measure distribution of nerve activity in the brain that is evoked by visual stimulus.
Studies of scalp potentials have shown they are related to certain visual perceptions.
Hence the brain-wave hat is able to detect what a subject thinks he sees or, in other words, measures the brain’s visual acuity.
 

If sentient extraterrestrials invest heavily in bionics, the brain/machine interface will become all-important. Much research is now in progress in human laboratories to enable computers to "read minds." Dr. Lawrence Robert Pinneo at Stanford Research Institute, for example, has constructed a "thinking cap" which picks up the subject’s electrical brain wave activity via scalp electrodes, analyses them, and then translates them into action. Pinneo’s volunteers can move dots from side to side on a computerized television screen, or run an object through a video maze, simply by thinking.2365 The executive computer can also recognize words, spoken aloud or silently thought (it makes no difference), by comparing them to prerecorded characteristic brain wave patterns of the particular subject.2662

Bionic ETs with computer implants
will have access to virtually all
knowledge possessed by their
civilization — mathematical, physical,
medical, psychological, and cultural.

Dr. Grey Walter at the Burden Neurological Institute in Bristol, England, has devised a similar computer-directed brain reading apparatus which operates as a remote controlled TV channel selector. By sheer force of thought, subjects can cause pictures to change or to hold on a television screen placed before them.92

Biocybernetic links

Speaking at the 1976 annual AAAS Conference, Dr  Adam Reed claimed that within fifty years miniaturized computers implanted under the scalp will be programmed to read and speak the electrochemical language of the human brain. In ten years — by 1986 — Reed believes we will have cracked the code the brain uses for information processing.

According to one science writer, "once that’s done, information can be fed directly into the brain’s central processing unit without going through peripheral equipment such as eyes and ears. You don’t read a book: the computer literally squirts its contents into your head."2664 To achieve these results, it is estimated that at least 100,000 electrodes/mm2 will be required in the implanted matrix (Figure 16.2).

Alien cyborgs outfitted with such "biocybernetic links" would be able to plug into modular units containing vast quantities of data in specialized areas. Internal or external storage devices could increase memory capacity by a billionfold.

Information can be fed directly into the brain’s
central processing unit without going through
peripheral equipment such as eyes and ears.

You don’t read a book — the computer
literally squirts its contents into your head.

Bionic ETs with computer implants will have access to virtually all knowledge possessed by their civilization — mathematical, physical, medical, psychological, and cultural. Alternatively, each individual could have an on-line radio link to a mammoth external computer intelligence — one need only think of some problem, request a solution, and patiently wait for the answer to appear in his thoughts moments later.

Electronic telepathy

Like telephone conference calls, ETs may be able
to link minds together through an electronic
medium to confer rapidly and obtain solutions
to particularly complicated dynamic problems.
Alien astrocyborgs may send their eyes, ears, arms
and legs wandering through space or across the
surface of a world, leaving their minds safely at home.

Such systems would also make possible a form of practical electronic "telepathy." Messages and other information might be dispatched from one brain to the master computer network, and then relayed on to any other biocybernetically equipped brain. Like telephone conference calls, ETs may be able to link minds together through an electronic medium to confer rapidly and obtain solutions to particularly complicated dynamic problems. And if a generalized, mathematical computer language is used in the external system, this may also provide an ideal channel for interspecies communication when first contact occurs.

Teleoperators

Of course, there’s really no need for fragile organic brains to venture out into wild foreign environments. Detachable bionic senses and effectors — called "teleoperators" — may be sent out to explore strange planetary surfaces while the alien’s flesh-and-blood brain remains safely in geosynchronous orbit high above. If ETs are receiving data via biocybernetic channels, what difference does it make whether the bionic eyeball which is doing the actual seeing is located in the eye socket of the skull or halfway around the planet? Except for minor time delays due to the finite speed of radio wave propagation, perception would be as instantaneous on "local" as on "remote." Alien astrocyborgs may send their eyes, ears, arms and legs wandering through space or across the surface of a world, leaving their minds safely at home.

16.3.3 Enter the Robot? (aka. Uploading)

Might extraterrestrial biotechnologists
be able to transfer personality and
consciousness into virtually indestructible
and immortal bionic bodies?

What about the possibility of totally bionic brains? Might extraterrestrial biotechnologists be able to transfer personality and consciousness into virtually indestructible and immortal bionic bodies? In theory, there are no technical objections to "total prosthesis," as it is sometimes called. Using advanced atomic or molecular electronics, fully synthetic brains which function as well as or better than the originals can easily be imagined. However, one major difficulty is frequently overlooked.

In most schemes, the subject’s brain contents are somehow "read out" and recorded using sophisticated high-capacity computer data storage devices. This data is later played back and imprinted upon the tabula rasa bionic brain. The mortal flesh-and-blood organ is then replaced by the immortal synthetic one in the cyborg body. Upon awakening, it is discovered that the words, thoughts, and behavior of the new entity are indistinguishable from those of the original in every way.

But it is not the original! The cyborg is only a copy. A duplicate person has been created and the original (presumably) destroyed — its sentience, its self-awareness, its personal consciousness. The new bionic brain, perhaps graced with a blissful continuity of memory, may not be aware of the change at all. But the original self is dead nevertheless. (The author, for one, would hesitate to accept such immortality by proxy.)

Transfer from biological to synthetic

This fundamental problem is difficult, but by no means impossible, to resolve. It may turn out to be relatively easy to transfer from a biological to a synthetic brain without any loss of self or interruption of consciousness in the original. Dr. Jonathan Boswell, a nuclear physicist at the University of Virginia, recently gave me one simple example of such a process:

Placed in direct contact with the bionic brain,
the two minds would begin to share the
thinking function. Ultimately, when the old
hulk of the body finally shrivels up and dies,
the shared mind lives on without interruption
in the synthetic brain.

I visualize the process of consciousness transfer as taking many years. First, biocybernetic electrodes would be implanted permanently in the brain of the aging patient. Many of them, so that the data pathways are wide. As the body decays — let us suppose it first goes blind — the consciousness inside finds that it can "see" through the cameras of the machine it's connected to. Later, it could hear, touch. … Placed in direct contact with the bionic brain, the two minds would begin to share the thinking function. Ultimately, when the old hulk of the body finally shrivels up and dies, the shared mind lives on without interruption in the synthetic brain.2665

Neuron assembly simulation

Artificial intelligence expert Hans Moravec has come up with a somewhat more elaborate scheme:

As soon as you are satisfied, the simulation
connection is established firmly, and the now
unconnected clump of neurons is removed…

Though you have not lost consciousness,
or even your train of thought, your mind has
been removed from the brain and transferred
to the machine.

You are in an operating theater, and a brain surgeon (probably a machine) is in attendance. On a table next to yours is a potentially human equivalent computer, dormant now for lack of a program to run. Your skull, but not your brain, is under the influence of a local anaesthetic. You are fully conscious. Your brain case is opened, and the surgeon peers inside. Its attention is directed at a small clump of about 100 neurons somewhere near the surface. It examines, nondestructively, the three dimensional structure and chemical makeup of that clump with neutron tomography, phased array radio encephalography, etc., and derives all the relevant parameters. It then writes a program which can simulate the behavior of the clump as a whole, and starts it running on a small portion of the computer next to you. It then carefully runs very fine wires from the computer to the edges of the neuron assembly, to provide the simulation with the same inputs the neurons are getting. You and it check out the accuracy of the simulation. After you are satisfied, it carefully inserts tiny relays between the edges of the clump and the rest of the brain, and runs another set of wires from the relays to the computer. Initially these simply transmit the clump’s signals through to the brain, but on command they can connect the simulation instead. A button which activates the relays when pressed is placed in your hand. You press it, release it and press it again. There should be no difference. As soon as you are satisfied, the simulation connection is established firmly, and the now unconnected clump of neurons is removed.

The process is repeated over and over for adjoining clumps, until the entire brain has been dealt with. Occasionally several clump simulations are combined into a single equivalent but more efficient pro gram. Though you have not lost consciousness, or even your train of thought, your mind has been removed from the brain and transferred to the machine. A final step is the disconnection of your old sensory and motor system, to be replaced by higher quality ones in your new home. This last part is no different than the installation of functioning artificial arms, legs, pacemakers, kidneys, ears and hearts and eyes being done or contemplated now.3233

  Advantages of neuron  
   assembly simulation   

Click for Synopsis   
Your machine has a speed control
■ Initially set to "slow," but now set to "fast"
■ You can communicate, react and think at a thousand times your former rate
The machine has a port
■ Enables the changing program that is you to be read out, nondestructively
■ Permits new portions of the program to be read in
■ Conveniently examine, modify, improve and extend yourself
in ways currently completely out of the question
Your entire program can be copied
■ Into a similar machine, resulting in two thinking, feeling versions of you
(or a thousand, if you want)
■ Mind can be moved to computers better suited for given environments
■ Or simply technologically improved
■ Far more conveniently than the difficult first transfer
■ Copied to a dormant information storage medium such as magnetic tape
If machine you inhabit is fatally clobbered
■ A copy of this kind can be read into an unprogrammed computer
resulting in another you, minus the memories accumulated since the copy was made
■ With frequent copies, the concept of personal death is virtually meaningless
Essence of you is an information packet
■ It can be sent over information channels
■ Your program can be read out
■ Radioed to the moon and infused there into a waiting computer
■ This is travel at the speed of light
■ The copy that is left behind could be shut down until the trip is over
■ Then, program representing you with lunar experiences is radioed back
and transferred into the old body
■ If the original were not shut down during the trip, there would be two separate
versions of you with different memories for the trip interval
Merging should be possible
■ It should become possible to merge two sets of memories
To avoid confusion, they would be carefully labeled as to which had happened where
just as our current memories are usually labeled with the time of the events they record
Merging also between different persons.
■ Mergings can be selective involving some of the other person's memories and not others
Very superior form of communication
■ Memories, skills, attitudes and personalities can be rapidly and effectively shared
Advantages of neuron assembly simulation

Moravec then goes on to point out the many advantages that would become apparent as soon as the process was complete:

Somewhere in your machine is a control labeled "speed." It was initially set to "slow," to enable the simulations to remain synchronized with the rest of your old brain, but now the setting is changed to "fast." You can communicate, react and think at a thousand times your former rate.

Major possibilities stem from the fact that the machine has a port which enables the changing program that is you to be read out, nondestructively, and also permits new portions of the program to be read in. This allows you to conveniently examine, modify, improve and extend yourself in ways currently completely out of the question. Or, your entire program can be copied into a similar machine, resulting in two thinking, feeling versions of you. Or a thousand, if you want. And your mind can be moved to computers better suited for given environments, or simply technologically improved, far more conveniently than the difficult first transfer. The program can also be copied to a dormant information storage medium, such as magnetic tape. In case the machine you inhabit is fatally clobbered, a copy of this kind can be read into an unprogrammed computer, resulting in another you, minus the memories accumulated since the copy was made. By making frequent copies, the concept of personal death could be made virtually meaningless. Another plus is that since the essence of you is an information packet, it can be sent over information channels. Your program can be read out, radioed to the moon, say, and infused there into a waiting computer. This is travel at the speed of light. The copy that is left behind could be shut down until the trip is over, at which time the program representing you with lunar experiences is radioed back, and transferred into the old body. But what if the original were not shut down during the trip? There would then be two separate versions of you, with different memories for the trip interval.

When the organization of the programs making up humans is adequately understood, it should become possible to merge two sets of memories. To avoid confusion, they would be carefully labeled as to which had happened where, just as our current memories are usually labeled with the time of the events they record. This technique opens another vast realm of possibilities. Merging should be possible not only between two versions of the same individual but also between different persons. And there is no particular reason why mergings cannot be selective, involving some of the other person’s memories, and not others. This is a very superior form of communication, in which memories, skills, attitudes and personalities can be rapidly and effectively shared.3233

16.4 Machine Life
16.4.0 Machine Life

Table 16.3 Molecular Fineness and the Thermodynamic Significance

of Patterns of Information (modified from Morrison1704)

table 16 3 molecular fineness thermodynamic significance 400
How much life is present

Can machines live? Evolve? Think? Many scientists would answer in the negative. Gears, relays, and integrated circuits certainly aren’t alive in the traditional sense. Evolution typically involves reproduction and natural selection, but no Earthly machines are known to reproduce themselves. And, it is said, cold steel cannot cogitate.

From the xenological point of view, however, we’ve already determined that the most useful definition of life involves the concept of negative entropy, or negentropy.

That is, to be considered "alive" an entity must:

  • Feed on negentropy (absorb order from the environment)
  • Store negentropy (create order within itself)

Figure 16.3 Microstructure in Machine Lifeforms and

Biological Lifeform Inhabiting the Planet Earth

figure 16 3 microstructure in machine and biological lifeforms 400

The amount of stored information in a living organism determines exactly how alive it is.

Microstructure in machine and biological lifeforms

Philip Morrison at MIT has taken a first stab at a quantitative analysis of "how much life" is present in any entity of specified complexity.

It will be recalled from Chapter 6 that a refrigerator or other similar contemporary machine technically is "alive" by our definition, because it feeds on negentropy and uses this to create internal order.

But most machines "alive" today aren’t very alive because they store only miniscule amounts of information at the molecular level.

Morrison has shown that patterns imposed on lumps of inert matter will not begin strongly to affect the matter thermodynamically "until the pattern is constructed with molecular fineness."1704

His calculations, summarized in Table 16.3, pertain to an hypothetical black-and-white
checkerboard pattern superimposed on a slab of otherwise inert matter.

The need for a biochemistry as a prerequisite
of organic life is far less compelling for
beings of purely artificial construction.

As such creatures perhaps can be modified or
repaired simply by replacing modular parts,
the only fundamental requirement appears to be
Morrison’s "molecular fineness of construction."

The distinction between biological and mechanical
life be comes quite blurred — are not machines
constructed of iron and silicon with molecular
patterns examples of "ferrosilicon-based lifeforms"?

We may view the last column of Table 16.3 as representing, in a sense, the intensity of life achieved by an information-laden pattern imposed on inanimate matter, Clearly, the finer the pattern (Figure 16.3), the more "alive" is the entity.

By implication, we cannot concede that machines are "very alive" until their components are constructed with molecular fineness. Only then will the information storage in machines be comparable to those found in biological lifeforms.

The need for a biochemistry as a prerequisite of organic life is far less compelling for beings of purely artificial construction. As such creatures perhaps can be modified or repaired simply by replacing modular parts, the only fundamental requirement appears to be Morrison’s "molecular fineness of construction." The distinction between biological and mechanical life be comes quite blurred — are not machines constructed of iron and silicon with molecular patterns examples of "ferrosilicon-based lifeforms"?

16.4.1 Artificial Intelligence
Turing Test

According to the "Turing Test,"
a computer is intelligent if a man is
unable to distinguish it from another
human being by talking to it over
a teletype communications link.

This is the ultimate objective test:
If an entity speaks and acts like a man,
presumably it is just as intelligent.

Intelligence may be broadly defined as any system capable of processing information — a negentropic ordering process of higher capacity than life itself. It is of critical significance that the actual physical form of the system is of comparatively little importance to what is taking place. The ability to reason — to think — is not a property of biological organisms alone. Rather, it is a property of specialized, highly-organized, complex patterns. Whether these patterns find expression in biological, artificial, extraterrestrial or even nonmaterial form is largely irrelevant to the fact of intelligence.

Time does not permit a detailed discussion of the arguments favoring the proposition of intelligent thinking machines. The objections are many, but their refutations are sound.* Projecting the advances in human computer technology over the past century into the century ahead, many leading scientists are now predicting the creation of artificial machine intelligence of extremely high order. And if we can do it, so can ETs.

Many decades ago an English mathematician named Alan Mathison Turing defined a crucial test to prove the existence of machine intelligence.2667, 3698  According to the "Turing Test," a computer is intelligent if a man is unable to distinguish it from another human being by talking to it over a teletype communications link. This is the ultimate objective test: If an entity speaks and acts like a man, presumably it is just as intelligent.

To date, no machine on Earth has passed the generalized Turing Test. However, the Test has been passed by computers restricted to limited areas of discourse or to certain well-defined human emotional or psychiatric states.


* Cynics and the otherwise unconvinced are referred to Armer,957 Clarke,55, 81 Cosma,896 George,952 McCarthy,85 Michie,953 Puccetti,71, 977 Putnam,1803 Raphael,2687 Rose,583 Sagan,318, 2552 Turing,955 and Wesley.1717

Conversation with PARRY

Are you connected with the Mafia?


How do they know you?


Why do they?


What do they have against you?


What for?


Are you sure of all this?


I am doing my best.


(Silence)


You seem hostile to me.


I am sorry.


Don’t you trust me?


Okay, tell me more about the Mafia.

YOU KNOW, THEY KNOW ME.


THEY SPY ON ME.


THEY WANT TO GET FALSE EVIDENCE TO FRAME ME.


THEY ARE OUT TO GET ME.


I HAVE INCRIMINATING EVIDENCE AGAINST THE MAFIA.


YOU DON’T BELIEVE ME?


(SILENCE)


CAN’T YOU THINK OF A DECENT QUESTION TO ASK?


SOME OF YOUR REMARKS ANNOY ME.


FORGET THE EXCUSES, YOU GUYS ARE ALL ALIKE.


I HAVE GOOD REASON TO BE THIS WAY.


THEY KNOW WHAT I’M DOING.

For instance, in the early 1970’s Dr. Kenneth Mark Colby at Stanford University created a program called PARRY that imitates the verbal behavior of a human paranoid. The system was designed to give psychiatry students useful experience in talking to severely mentally ill patients. PARRY is supposedly 28 years old, unmarried, and a postal clerk. He is sensitive about his looks, education, religion and sex. He once attacked a bookie for not paying a bet at the racetrack, and he’s afraid that the underworld is out to get him. A sample conversation with PARRY at right (his words in capitals):

Can PARRY pass the Turing Test? Forty-eight psychiatrists were given paired transcripts of conversations with the computer and with a genuine human paranoid mental patient. Only half of the doctors could distinguish man from machine. Realizing that psychiatrists might not be able to recognize the subtle cues that might tip off a computer science expert, Dr. Colby sent similar transcripts to a hundred members of the Association for Computing Machinery. Of the 67 respondents, 32 guessed correctly and 35 guessed wrong.2670 On his own, very limited turf, PARRY passed the specialized Turing Test with flying colors.

World class checkers

Besides mimicking human psychoses, computers have been programmed to play intellectual games as well as men. Machines are now world class checkers players. In 1965, A. L. Samuel estimated that only a dozen of the world’s checkers masters could defeat a program he’d written.2673 Far more challenging, however, is the complex game of chess.

Chess 4.5

Attempts to devise computer programs to play chess have been underway for decades.2674, 2675 In August of 1968, David Levy, then Chess Master of Scotland and later International Master, made a bet of $2100 with several computer scientists that no machine program could beat him at regulation chess within ten years. In the early 1970s, Lawrence R. Atkin and David J. Slate of the Computation Center at Northwestern University wrote "Chess 4.5." This program held the United States computer chess championship title in 1977.

In the Spring of that year, Levy sat down with Chess 4.5 to play a regulation 40-moves-in-two-hours game. Levy won, but the machine made him work hard for it. Then came the real shocker. After the regular match was concluded, the two contestants played an off-the-record "blitz" game in which each side was allowed only 5 seconds per move. Chess 4.5 won handily.

Experts estimate the official ranking of Chess 4.5 in regulation play to be about 2000-2200 points on the standard scale, as compared to 2325 for Levy and 2690 for the current World Champion. It is believed that in "blitz" chess the computer improves its rating by 200-400 points over human opponents.2676 Thus, in blitz matches at least, Chess 4.5 is already at the grandmaster level.

Conversations with SHRDLU

Earthly computers may be quite clever, but how much can they really understand what is communicated to them? Dr. Terry Winograd at MIT has developed an amazing machine program, named SHRDLU. This complex system was designed for the express purpose of understanding English.2696

Like a small child secluded in a playroom, SHRDLU inhabits a world that includes a toy box, building blocks and pyramids of various sizes colored blue, green, and red. Mechanical arms and mobile camera eyes give SHRDLU the ability to stack or assemble the blocks in any desired configuration on the playroom floor. Most important, the computer responds to commands and gives answers to questions in an intelligent manner.* Extracts from conversations between Winograd and SHRDLU (in capitals) follow.

SHRDLU can understand spatial relationships:

How many blocks are not in the box?


Is at least one of them narrower than
the one which I told you to pick up?


Is it supported?


Can the table pick up blocks?


Can a pyramid be supported by a block?


Stack up two pyramids.

FOUR OF THEM.


YES, THE RED CUBE.
 


YES, BY THE TABLE.


NO.


YES.


I CAN’T.

SHRDLU can identify its own motives:

Had you touched any pyramid before you
put the green one on the little cube?


When did you pick it up?
 


Why?


Why did you do that?


Why did you clear off that cube?


Why did you do that?
 


Why did you do that?

YES, THE GREEN ONE.
 


WHILE I WAS STACKING UP THE RED CUBE, A
LARGE RED BLOCK AND A LARGE GREEN CUBE.


TO GET RID OF IT.


TO CLEAN OFF THE RED CUBE.


TO PUT IT ON A LARGE GREEN CUBE.


TO STACK UP THE RED CUBE, A LARGE
RED BLOCK AND A LARGE GREEN CUBE.


BECAUSE YOU ASKED ME TO.

SHRDLU can assimilate novelty in its environment:

Is there a steeple?


A "steeple" is a stack which contains
two green cubes and a pyramid.


Are there any steeples now?


Build one.
 

SORRY, I DON’T KNOW THE WORD "STEEPLE."


I UNDERSTAND.
 


NO.


OK.
{the machine does so}

SHRDLU makes assumptions to help resolve
ambiguities in speech:

Call the biggest block "superblock."


Have you picked up superblock since
we began?


Is there anything to the right of
the red pyramid?


Why did you drop it?
 

OK.


YES.
 


YES, FOUR THINGS: THE BOX, THE RED CUBE, THE BLUE
PYRAMID, AND THE BLOCK NAMED SUPERBLOCK.


BY "IT," I ASSUME YOU MEAN SUPERBLOCK…
I CAN’T EXPLAIN A NONEXISTENT EVENT.

Can Winograd’s program really think? Is it truly intelligent? We aren’t permitted to dismiss SHRDLU solely because it's "just a computer." The Turing Test for machine intelligence is an objective one: If the entity appears to be thinking, Turing maintained, it is pointless to deny that it is thinking.


* The system, while not perfect, is capable of carrying on a real-time discourse. Analysis of and response to each sentence requires from 5-20 seconds.175

Intelligence may be a necessary adjunct to complexity

Some scientists believe that intellect is
the direct consequence of the enormous
intricacy of interactions among ten billion
active neural components.

Although SHRDLU passes the Test only in a limited way, recent developments in the artificial intelligence field have clearly demonstrated that computers can be taught to interpret meanings by the same processes that humans use.2851 Dr. A.M. Andrew, cyberneticist at the University of Reading, England, predicts:

Turing’s test will be passed … with no restrictions on topics of conversation or manner of reply by the year 2000 A.D. However, even then the computer will seem like a person behaving rather stiffly and refusing to be drawn into small talk. Perhaps by 2050 A.D. a computer will seem to be someone with whom a joke can be shared, and with whom the conversant identifies to the extent that it becomes important not to hurt the other’s feelings.2707

If alien electronic artificial intellect is
possible, how physically small might it be?

The theoretical lower limit of cell size is
about 400 Angstrom, a bit smaller than
the tiniest known living organism.

A brain with 1010 neurons of this
size would neatly fill a minute cube
one-tenth millimeter on a side.

It appears not only possible but probable that many different sentient extraterrestrial races will develop advanced artificial intelligences. It is not yet clear exactly how complex these systems must be. Dr. Marvin Minsky of the MIT Artificial Intelligence Laboratory claims that 106 bits would probably be enough to create true intellect — provided they "were all in the right place."22 Winograd’s program has about this many — a million bits — and the spunky Viking Mars Lander computers carried preprogrammed instructions amounting to a few million bits. In the animal world, this would correspond roughly to the intelligence level of amphibians such as frogs. Says Minsky of Winograd’s SHRDLU:

We see here a computer program that has a small but noticeable fraction of the intelligence of humans. The fraction is somewhere between 10-6 and 10-1. I cannot conceive that it would take 1012 bits {mammal and primate brains) to hold a superintelligent being.22

Some scientists believe that intellect is the direct consequence of the enormous intricacy of interactions among ten billion active neural components. Experiments performed by Dr. S.A. Kauffman at MIT in 1961 lend some support to this notion. Kauffman wanted to know what would happen if a large number of arbitrary computer components — "electronic gates" — were connected to each other at random, with inputs and outputs linked higgledy-piggledy throughout the network. With 100 units, one might suppose that approximately 2100 (or 1030) different states would be possible, thus rendering the system totally unpredictable. But Kauffman discovered that for a 100-element network there are rarely more than ten distinct cycles of about ten transitions each.2678 This result has since been confirmed by others,1785 and demonstrates that intelligence may be a necessary adjunct to complexity.

If alien electronic artificial intellect is possible, how physically small might it be? The theoretical lower limit of cell size is about 400 Angstrom, a bit smaller than the tiniest known living organism (the PPLO). A brain with 1010 neurons of this size would neatly fill a minute cube one-tenth millimeter on a side.

Energy consumption / efficiency of data-processing devices

Table 16.4 Energy Consumption and Efficiency of

Natural and Artificial Data-Processing Devices

table 16 4 energy consumption and efficiency of data processing devices 500px

But artificially designed alien microbrains theoretically could be vastly smaller still. Using molecular electronics with components on the order of 10 Angstrom in size, 1010 microneurons could be packed into a space of a few microns. This is small enough to hide inside a bacterium, a fact which may have several very interesting consequences.2873 Also, if a brain the size of the head of a pin were constructed, it could house as many as ten million times as many neurons as a single human brain. Alternatively, an intelligent space probe the size of a grapefruit might carry a "city" of billions of advanced cybernetic intellects.

Energy per binary act

The great late Princeton mathematician von Neumann once calculated the power consumption of brains designed with maximum efficiency, using thermodynamic criteria.1726 There is a certain minimum amount of energy that must be expended to accomplish a single "binary act," or simple decision, within a brain.

The relative efficiency of artificial devices
is just now passing that of the biological
ones, here on Earth, but terrestrial
technology clearly still has a long way to go.

In Table 16.4, this value is compared both with human biological neurons and with a variety of modern electronic devices. The relative efficiency of artificial devices is just now passing that of the biological ones, here on Earth, but terrestrial technology clearly still has a long way to go.

Intelligent alien robots may have more closely approached, or already achieved, the ultimate thermodynamic limit of cerebral efficiency.

16.4.2 Robots and Robotics

The word "robot" itself comes from a 1920 play
written by the late Czech author Karel Capek
entitled Rossum’s Universal Robots.

In this early science fiction tale of the future,
sentient robots revolt against human-enforced
slavery and conquer the world themselves.

Robots are now on the human scene in all but their most advanced forms. One writer has observed that "robots are at about the same stage as electronic calculators about a decade ago… . Specialists in the field suggest that ten years from now robots will be as common as calculators are today."2681

The word "robot" itself comes from a 1920 play written by the late Czech author Karel Capek entitled Rossum’s Universal Robots. In this early science fiction tale of the future, sentient robots revolt against human-enforced slavery and conquer the world themselves.

One of the first writers with the courage to portray intelligent mechanical beings as benign, or at least indifferent, was Dr. Isaac Asimov. His well-known Three Laws of Robotics — intended to be incorporated into the basic psychology of every sentient machine — were designed to prevent a revolt against biological creators such as was envisioned by Capek:

Asimov's Three Laws of Robotics

First Law:

Second Law:

Third Law:

A robot may not injure a human being, or, through inaction, allow a human being to come to harm.

A robot must obey the orders given it by human beings except where such orders would conflict with the First Law.

A robot must protect its own existence as long as such does not conflict with the First or Second Laws.2682

While these rules may guide human planners, there is no guarantee that extraterrestrial robots will obey the Three Laws or any similar failsafe system. ETs may choose to give their automatons considerably greater freedom of action, especially if they are the products of "total prosthesis" (biological consciousness transferral). Mechanicals from other worlds designed to perform military, emergency rescue, or political functions may require considerably more autonomy than Asimov’s Laws would permit.

Figure 16.4 Humanoid Robot-Building Technology:

Terrestrial State-of-the-Art

Figure 16.4 Humanoid Robot-Building Technology

Figure 16.4 Humanoid Robot-Building Technology: Terrestrial State-of-the-Art
Century I

Century I is a 2-meter, 300-kilogram (7-foot, 650-pound) bullet-proof automated security guard. The $75,000 robot was unveiled at the 1977 annual seminar of the American Society for Industrial Security.

The humanoid’s sensors detect movement, body heat, or noise and lock onto the source. At speeds up to 30 kph (20 mph), Century I closes on its quarry. When it gets within about 3 meters, it orally instructs the intruder to halt with an imperious voice.

If disobeyed, the robot gets tough. Standard equipment includes an ultrasonic sound transmitter that causes extreme pain in the inner ear. A blinding strobe light, an electronic pistol that shoots powerful shocks, and a spray gun filled with laughing gas are also available. While admitting that Century I could be programmed to kill, Anthony J. Reichelt of Quasar Industries Inc. (Rutherford, N.J.) added that his firm plans to use only "nonlethal restraint" in its machines.

Quasar is also developing a $125,000 Century II robot for the U.S. Army. "Once he’s put on program," explained inventor Reichelt in regard to the improved model, "nobody can stop him."2702

Klatu

Another product of Quasar Industries, Klatu is seen as a possible prototype for the first "domestic android." At 1¼ meters tall and 80 kilograms (5 feet, 180 pounds), the robot reputedly may be programmed to accept a wide variety of household chores.

According to Reichelt, president of Quasar, Klatu can: Vacuum floors, greet guests and take their coats, serve drinks and dinner, guard the house, walk the dog, clear dishes from the table, wash windows, speak "intelligently" with a 250-word vocabulary, and play nursemaid to the children and the bedridden. Robotologists and other experts in the scientific community are skeptical.

The price — a cool $4000.2703

Leachim

Grade school students at Public School 106 in the Bronx receive instruction from a robot substitute teacher. The picturesque 1¼-meter, 90-kilogram (5'5", 200-pound) automaton with black plastic arms and legs was created by Dr. Michael Freeman for only $1000. (The legs are motorized, but the robot is chained to a table for security.)

The humanoid’s brain is a computer, made partly from components cannibalized from an RCA Spectra 70. Leachim has memorized parts of Compton’s Encyclopaedia, Webster’s New World Dictionary, a Ginn science book, a thesaurus and a Macmillan reading series, as well as the national anthem, the Pledge of Allegiance, Aesop’s fables, a round of jokes, a few words in Spanish, and detailed biographical and educational information for each student.2693

Humanoid robot-building technology

Terrestrial robotics technology is actually fairly advanced in the area of physical locomotion (Figure 16.4). Human roboticists at Stanford Research Institute (SRI) have constructed an computer-directed automaton with wheels, two retractible arms, and a television camera mounted in its "head." The device, nicknamed "Shakey," is free to roam about a room strewn with objects of various shapes and sizes. The SRI robot can be programmed to perform specific lifting, moving and stacking operations. (E.g., "Pick up the smallest cube and take it to the doorway."1779

The Russian automated lunar rover Lunakhod is a mobile eight-wheeled robot with TV camera eyes, able to navigate the surface of the Moon. Soviet scientists also are developing a spider-like surface exploratory vehicle that will be able to cross obstacles impassable by wheeled or caterpillar-tracked machines. This device, now under development at the Leningrad Institute of Aviation Instrument Makers, has six legs, a computer "brain," and a laser eye that scans ahead for trouble.1138 It reportedly can negotiate steep slopes, stairs, narrow corridors with sharp turns, and landscapes littered with stones or fallen trees.2694

Mechanical feeding

Mechanical "feeding" has also been accomplished. Robots have been designed that are capable of searching for "food" and thus of maintaining their own active existence. Dr. W. Grey Walter designed a small electronic turtle in his laboratory in Bristol, England, decades ago. Dubbed Machina speculatrix by its creator, Walter’s "machine lifeforms" each consisted of two tiny radio tubes, a photoelectric cell and a touch sensor, motors for crawling and steering, and a light bulb for "speaking," all hooked up to a miniature 6-volt storage battery.1783

Each robot exhibited various interesting behaviors. When the battery ran low, the turtle was programmed to hunt for its "hutch" where it could plug in and recharge.* When placed in front of a mirror, the device displays a primitive form of self-recognition. An encounter between two mechanical creatures is described by Walter thus: "Each, attracted by the light the other carries, extinguishes its own source of attraction, so the two systems become involved in a mutual oscillation, leading finally to a stately retreat."2106 Later models were equipped with microphones so they could respond to whistles. More complicated circuitry allowed more variable behavior as well as the ability to "learn."60 With a behavior repertoire attributable to no more than 1000 bits, the intelligence of Machina speculatrix probably rivals that of the rotifer.

We’ve seen that emotions and intellect can
be impressed upon artificial structures.

There appear to be no real limits to the
complexity of organization and behavior
that might be displayed by alien robots.

Indeed, extraterrestrial automata
may even have the ability to reproduce.

The purpose behind Walter’s work was to demonstrate that quite simple machines could fairly well mimic the goal-seeking ability of animals. All the major attributes of life on Earth — feeding, metabolizing, mobility, response to stimuli and so forth — can and have been designed into various machines built by humans.1782 We’ve seen that emotions and intellect can be impressed upon artificial structures. There appear to be no real limits to the complexity of organization and behavior that might be displayed by alien robots. Indeed, extraterrestrial automata may even have the ability to reproduce.85, 956

Self-reproducing machines

Von Neumann demonstrated during the 1940’s that self-reproducing machines are quite possible in principle.1726 Basically, the problem is to find the proper parts and to know how to put them together. Von Neumann envisioned a machine that could move around in a special stockroom, selecting the pieces required to build another machine exactly like itself — and then doing so. Such a device necessarily consists of two parts: One part to build a duplicate copy, and another part able to program the duplicate so it can make more copies too. (This is analogous to the distinction between phenotype and genotype in biology.2364) According to one computer scientist, such a reproducing system could be as small as 150,000 bits of information.1737 [Note added: A general review of kinematic self-replicating machines was published by the author in 2004 and is available online at http://www.MolecularAssembler.com/KSRM.htm.]

A large population of such organisms would constitute an ecology. They will evolve. Wrote von Neumann:

If there is a change in the description … the system will produce, not itself, but a modification of itself. Whether the next generation can produce anything or not depends on where the change is. So, while this system is exceedingly primitive, it has the trait of an inheritable mutation, even to the point that a mutation made at random is most probably lethal, but may be nonlethal and inheritable.1726

Sentient alien automata thus may be "alive" both in the popular as well as the technical sense.


Do it yourself

* Anyone interested in building such a device should consult Huber’s article "Free Roving Machine," which contains specifications and circuit diagrams for a similar system.1784 A more ambitious design for a "mechanical pet" may be found in Heiserman’s Build Your Own Working Robot.2683

16.4.3 Machine Evolution
Machine Evolution

Van Loon’s Law


The amount of mechanical development will
always be in inverse ratio to the number of
slaves at a country’s disposal.

The more slaves that are available to do
drudge work, the slower machines will evolve.

Tools have been used on Earth for many millions of years. Baboons use handy sticks to pry up tasty roots and grubs. Thorns are used by birds to probe for insects. Wasp and bee hives are splendid examples of architectural perfection. But each of these represent a static technology. Only with the advent of higher intelligence, the mind of man, could tools — machines — really begin to improve and evolve.

Van Loon’s Law

This is not to say that machine evolution must occur among all sentient extraterrestrial races. Consider the well-known Van Loon’s Law, which states: "The amount of mechanical development will always be in inverse ratio to the number of slaves at a country’s disposal."972 The more slaves that are available to do drudge work, the slower machines will evolve.

The ancient Greeks, with a population of only five million freemen as against twelve million slaves, neither needed nor invented any startlingly new labor-saving contrivances. The Romans, too, developed no power engines and made few significant improvements in machines or tools. It is said that the emperor Vespasian, when offered a mechanical device with which to cheapen construction work, bought the only model and had it destroyed.

Still, we may expect that many ET races will develop machines because they make the business of survival and reproduction easier. Barring technological stasis, three distinct classes of machine evolution may be clearly identified:

  • Directed Evolution
  • Participative Evolution
  • Natural Evolution
Directed Evolution

Directed Evolution is mechanical development
authorized, planned and executed wholly under
the direction of sentient biological lifeforms.

As organic beings successively design, build,
and test improved models of labor saving or
data-processing devices, these machines "evolve."

Directed Evolution is mechanical development authorized, planned and executed wholly under the direction of sentient biological lifeforms. As organic beings successively design, build, and test improved models of labor saving or data-processing devices, these machines "evolve."

The term is not inappropriate in this context. In the 20th century on Earth we have witnessed the explosive evolution of the automobile, airplane, radio, and digital computer. Each year new models come out. Improvements are added, troublesome parts deleted or modified. The least versatile or desirable machines become extinct, while the more adaptive ones survive and spawn new generations. The evolution of terrestrial machines, directed by man, is a fact. Elsewhere there must be machines evolving under the guidance of alien minds.

 Directed Evolution on Earth 

Click for Synopsis   
20th century's explosive evolution of machines
Examples:
Automobile, airplane, radio, and digital computer
■ Each year new models come out
■ Improvements are added
■ Troublesome parts deleted or modified
■ The least versatile or desirable machines become extinct
■ More adaptive survive and spawn new generations
■ Proceeds much faster than normal biological evolution
In just 1000 years, the tools of man have advanced
■ From axe and shovel to Saturn V moon rockets and 95-ton caterpillar earthmovers
■ This represents an increase in raw physical power of from four to six orders of magnitude
    over bare human muscle
■ Nature required 10-100 million years to achieve comparable results when giant dinosaurs
    evolved from their weaker ancestors during the Mesozoic
300 years for human stablemen to create a diminutive breed
of horse that bears remarkable similarity to ancient Eohippus

■ 30 million years of natural evolution partially unravelled in 300 years of directed evolution
■ Again a factor of about five orders of magnitude

Directed Evolution proceeds much faster than normal biological evolution. In just 1000 years, the tools of man have advanced from axe and shovel to Saturn V moon rockets and 95-ton caterpillar earthmovers. This represents an increase in raw physical power of from four to six orders of magnitude over bare human muscle. Yet Nature required 10-100 million years to achieve comparable results, when giant dinosaurs evolved from their weaker ancestors during the Mesozoic. Another example: It has taken 300 years for human stablemen to create a diminutive breed of horse that bears remarkable similarity to ancient Eohippus. The partial unraveling of 30 million years of natural evolution in only 300 years of directed evolution is again a factor of about five orders of magnitude.

As a rough guess, then, we might suppose that Directed Evolution may be anywhere from 104-105 times faster than natural evolution. Marvin Minsky claims it might be as much as a million times faster. This is, he says, because a sentient race "can combine separate improvements directly, where nature depends upon fortuitous events of recombination."92

If Directed Evolution is fast,
Participative Evolution must be even faster.
Participative Evolution occurs when the
sentient biological race turns over its
executive functions to an artificial intellect.

Further mechanical evolution then occurs
at the behest and under the direction of
an intelligent computer sentience.

If Directed Evolution is fast, Participative Evolution must be even faster. Participative Evolution occurs when the sentient biological race turns over its executive functions to an artificial intellect. Further mechanical evolution then occurs at the behest and under the direction of an intelligent computer sentience. We have already seen the benefits of participative evolution in connection with genetic engineering, as when man takes control of his own evolutionary development. Once flesh-and-blood creators abdicate their directive role, machines will participate in their own evolution.

Intelligence explosion

Dr. N.S. Sutherland, Professor of Experimental Psychology at the University of Sussex, believes it will be easier to engineer a superintelligent machine lifeform than to breed a more powerful biological one. If this turns out to be correct, alien civilizations may experience what some writers have termed an "intelligence explosion" — a chain reaction of rapidly increasing intellectual capacity and mental sophistication.1174 Computers on any world, claims Dr. Sutherland, could rapidly "bootstrap themselves on the experience of previous computers" to create advanced artificial intelligence almost instantaneously on evolutionary timescales. Such machines may quite literally lie beyond the comprehension of any biological being.

Participative Evolution

 Participative Evolution details 

Click for Synopsis   
We have already seen the benefits of participative evolution
■ in connection with genetic engineering
■ as when man takes control of his own evolutionary development

Once flesh-and-blood creators abdicate their directive role
■ machines will participate in their own evolution


Computers on any world
■ Could rapidly "bootstrap themselves on the experience of previous computers"
■ To create advanced artificial intelligence almost instantaneously on evolutionary timescales

Such machines may quite literally lie beyond the comprehension of any biological being


Participative Evolution should provide
■ The fastest means for improvement available to any race — mechanical or biological
As in Directed Evolution
■ Superior characteristics are accumulated by each successive generation
■ But since the executive intelligence is also improving by leaps and bounds
■ The rate of evolution actually accelerates
We can estimate how fast this will be
■ Man has begun to use his computers to design new machines as well as other computers
■ Total memory capacity of terrestrial artificial intelligences has gone from
a few thousand bits of information up into the ten terabit range (1013 bits)
■ A similar ten-billionfold rise in biological brain capacity — from primitive animals to man
has required on the order of one billion years of natural evolution on Earth
■ Participative Evolution proceeds perhaps 106-107 times faster than Natural Evolution
■ Or about 100 times faster than Directed Evolution

Participative Evolution should provide the fastest means for improvement available to any race, mechanical or biological. As in Directed Evolution, superior characteristics are accumulated by each successive generation. But since the executive intelligence is also improving by leaps and bounds, the rate of evolution actually accelerates.

We can estimate how fast this will be. In the last century man has begun to use his computers to design new machines as well as other computers. Total memory capacity of terrestrial artificial intelligences has gone from a few thousand bits of information up into the ten terabit range (1013 bits).583 A similar ten-billionfold rise in biological brain capacity — from primitive animals to man — has required on the order of one billion years of natural evolution on Earth. So we might guess that Participative Evolution proceeds perhaps 106-107 times faster than Natural Evolution, or about 100 times faster than Directed Evolution.

All of the above is not to imply that technologically advanced extraterrestrial civilizations must all be robotic, androidic, or bionic. There may be cultural taboos, mineral shortages, or fundamental biological reasons for the lack or slower pace of machine evolution on any given world. ETs may vary widely in their motivational structures, or may be so adaptive or immortal that they have no need for machines.

Still, we must remain alert to the possibility of advanced alien automata in the context of culture contact. For many extraterrestrial races, and perhaps our own, James Wesley’s prediction may prove chillingly accurate:

In terms of the 4½ billion years of carbon-based life on Earth, the advent of machines has been amazingly abrupt. Yet the evolution of machines is subject to the same laws as the evolution of ordinary carbon-based life. Machines have also evolved toward an increased biomass, increased ecological efficiency, maximal reproduction rate, proliferation of species, motility and a longer life span. Machines, being a form of life, are in competition with carbon-based life. Machines will make carbon-based life extinct.1717

Natural Evolution

Natural Evolution is the third and slowest
alternative for the emergence of machine
life on other planets.

In this case, automata evolve slowly
under the forces of natural selection in an
environment favoring their development.

The main problem is finding the right
environment.
"Robot evolution," Frederika said.
"After man was gone, the machines that
were left began to evolve."

Natural Evolution is the third and slowest alternative for the emergence of machine life on other planets. In this case, automata evolve slowly under the forces of natural selection in an environment favoring their development. The main problem is finding the right environment.

Poul Anderson, a well-known science fiction writer, has concocted an imaginative scenario that would readily permit natural robot evolution. In his story "Epilogue," human space travelers return to Earth after a hiatus of three billion years because of unusual relativity effects. They discover to their horror that Earth has been rendered sterile by global war. The planetary ecology is wrecked beyond repair; mankind died out when biology disintegrated around it. The spacemen descend to the surface for one last farewell look, and discover that the planet is teeming with life: Machine life.

"Robot evolution," Frederika said. "After man was gone, the machines that were left began to evolve."

Before the Traveler departed, self-reproducing machines were already in existence. Each had electronic templates which bore full information on its own design. I expect that hard radiation would affect them, as it affects an organic gene. The {floating sea-mining robot} rafts started making imperfect duplicates. Most were badly designed and foundered. Some, though, had advantages. For instance, they stopped going to shore and hanging about for decades waiting to be unloaded. Eventually some raft was made which had the first primitive ability to get metal from a richer source than the ocean: namely, from other rafts. Through hundreds of millions of years, an ecology developed. The land was reconquered. Wholly new types of machine proliferated.982

Spontaneous machine life

Machines with the ability to mine and reproduce may be turned loose on purpose by their alien biological creators. Evolving on the home planet or on some foreign world, these automata would quickly radiate into a multiplicity of machine species under the influence of normal selective forces. However, there may exist environments which don’t require any initial "pump priming" by a biological race. There might be a few locales in the Galaxy where machine life of some form can arise spontaneously much as carbon-based life did on Earth many eons ago.

Electromechanical life

Electromechanical life may be able to evolve on jovian worlds or at the surface of black dwarf stars. The chemistry of substances at very high pressures is well understood.1177 Many insulators become conductors at pressures above 105 atm. Experiments with metallic hydrogen — believed to constitute the core of Jupiter — show that there is a sharp transition in electrical resistivity from 108 down to 102 ohms between 1-3 million atm pressure.2684 Diamond, silicon dioxide (sand), and other common materials have been crushed into the metallic state around 106 atm. Semiconductors such as silicon and germanium collapse into a tin-like material and become electrical conductors under high pressure.

Superconducting organisms

Since different materials conduct differently, an ordered regime of metallized substances may become functional as a kind of primitive electronic intelligence. Evolution of such lifeforms could be possible at or near the Jovian core. Note that this environment will strongly favor machine life over carbon life. Sugar and most other carbohydrates become violently unstable above 50,000 atm, decomposing explosively to carbon dioxide and water.1177 Another possibility is that beings elsewhere may have evolved with superconductive brains. Polymeric sulfur nitride has been shown to be superconductive a low temperatures, and strands of this or related materials may comprise the nervous systems of low temperature creatures on other worlds.

But extreme coldness may not be required at all. A room temperature solution of the enzyme lysozyme, when subjected to magnetic fields in excess of 600 gauss, apparently exhibits distinct regions of superconductivity.2686 And other substances are known to be unidirectional conductors — a kind of one-dimensional metal. They may have the conductivity of copper in one direction yet are excellent insulators in the other two. According to V.L. Ginzburg of the Lebedev Physical Institute in Moscow; "It is not science fiction to assume that evolution on some other planet, evolution by the methods and materials we know, has given rise to superconducting organisms."22

Spontaneous complex electronic circuits

Complex electronic circuits eventually arise.

■ Photosensitive spots permit this "intelligence" to see

■ A piezoelectric crystal formation gives it a limited
    sense of touch.

■ Contact with sunlight generates solar power.

■ After much time has passed, the intelligence manages
    to establish "an immense number of dipoles along a
    polymer thread with regularly spaced charged groups
    along it" to form a sheet of contractile polymer.

■ Current passed along its length causes it to contract.

■ After sufficient effort, manipulatory appendages emerge.

■ The geographically-dispersed sentience sets itself
    the task of constructing a more complex, compact,
    and mobile physical form.


Eons old, a grey-skinned bloodless humanoid
lifts its sensors to the night sky and beholds
the glory of a billion suns.

Still another possible site for the spontaneous natural evolution of machine life might be the surface of a hot planet about the size of Mars at the orbit of Mercury. V.A. Firsoff claims that such a world could not hold on to an Earthly atmosphere for long and would soon shed all lighter gases. All gaseous components with molecular weight less than 30 would be lost. This results in a high-molecular-weight atmosphere, rich in hydrogen sulfide and, perhaps, such oddities as diborane, silane, and carbon disulfide. One planetary solvent, available in limited quantities, might be a form of phosphorus sulfide. P4S3 is the most stable of these.352

A porous surface and a network of caves are cooked in scalding sunlight. There is no oxygen, so free silicon is available at the surface in amorphous form.2192 Planetary rotation, coupled with temperature and pressure gradients, give rise to violent gales of variable composition. By day, the hot phosphorus-and arsenic-laden winds whistle through the surface caves which hide the layers of free silicon, "doping" it with excess electrons. At night the cooler boron-rich atmosphere "drifts" the substrate with electron holes.

Arbitrarily fine photosensitized patterns slowly crawl across the cave floors and walls as the sun passes overhead, due to the changing angles of intense solar radiation filtering through the porous ceiling. Countless random channels of N-doped and P-doped material are slowly carved over the millennia. Caves located near coastlines or on lakeside beaches are periodically flushed with rain and rising tides. Complex electronic "circuits" eventually arise.

Photosensitive spots permit this "intelligence" to see. A piezoelectric crystal formation gives it a limited sense of touch. Contact with sunlight generates solar power.2813, 2815 After much time has passed, the intelligence manages to establish "an immense number of dipoles along a polymer thread with regularly spaced charged groups along it" to form a sheet of contractile polymer.2685 (Drops in current across a cell membrane are thought to be able to move certain molecules in the membrane. It’s believed that sodium-ion-driven currents help bring about limb regeneration in salamanders and other small amphibians.) Current passed along its length causes it to contract. After sufficient effort, manipulatory appendages emerge. The geographically-dispersed sentience sets itself the task of constructing a more complex, compact, and mobile physical form.

Eons old, a grey-skinned bloodless humanoid lifts its sensors to the night sky and beholds the glory of a billion suns.

  Chapter 17 ♦ Interstellar Voyaging   
17.0 Interstellar Voyaging
immanuel kant


To a Type II stellar culture,
a mission to the stars will seem
no more unreasonable nor
expensive than Project Apollo or
the Space Shuttle seemed to us.

Many reputable Terran scientists have argued, or attempted to "prove," that starflight is impossible or at least grossly unfeasible. (See Asimov,1403 Morrison,2750 Oliver,2749 Opik,2748 Purcell,1024 Simons,2361 and von Hoerner,1025 to name just a few.)
However, in each case the only thing that was proven was that initial assumptions could be chosen to give the appearance of immense difficulty.

Acceleration

The fact is that without violating any of the principles of Einstein’s Theory of Relativity, an astronaut theoretically may travel anywhere in the known universe in less than a century — faster, if he can stand the acceleration. Strictly in accordance with the laws of physics as we understand them today, a physical object may be moved from any point A to any other distant point B in as short a period of time as is desired. If you have the energy, it’s just a problem in engineering.*

Strictly in accordance with the laws of physics
as we understand them today, a physical object
may be moved from any point A to any other
distant point B in as short a period of time as
is desired. If you have the energy, it’s just a
problem in engineering.
Total energy resources

As members of an emergent Type I civilization, we humans exhibit a natural tendency to measure the achievements of the future against the standards of the present and the limitations of the past. Dr. Edward Purcell, for example, has calculated that a 10-ton relativistic rocket traveling at 98% the speed of light over a 24 light-year round trip starcourse may require a propulsion system capable of handling 1018 watts of power. Since this is more than a hundred thousand times the current total output of humanity, such a proposition must be "preposterous"! Concludes Purcell, winner of the 1952 Nobel Prize in Physics: "All this stuff about traveling around the universe . . . belongs back where it came from, on the cereal box."

Matter of perspective

But let us look at this a bit more closely. Is a 1018 watt starship really preposterous? Even an early Type II stellar culture will have 1020 watts at its command. Humanity itself may well achieve this state of affairs just a few hundred years from now. Is it logical to assert that we would begrudge a mere 1% of our total energy output for an interstellar mission? It seems useful to recall that the mighty Saturn V rocket booster that carried twelve American astronauts to the moon developed more than 1011 watts in its power plant — which represented roughly 2% of humanity’s total annual power output at the time.

It’s simply a matter of perspective. To a planetbound, 1013 watt developing Type I culture such as ours, a 1018 watt interstellar vehicle appears a fearsome project indeed. But to a 1020 watt early Type II stellar culture, a mission to the stars will seem no more unreasonable nor expensive than Project Apollo or the Space Shuttle seemed to us.

And to a mature Type II civilization (1026 watts), the dispatch of a 10-ton starship to neighboring stellar systems will represent the same relative drain on total energy resources as driving a Volkswagen automobile to market represents against the entire planetary power output of Earth.


* A complete bibliography of interstellar travel and communications has been compiled by Dr. Robert L. Forward.1680 Preliminary programs for interstellar exploration by mankind have been developed by Forward,718 Gillfillan,2845 Stine,672 and the Project Daedalus Study Group of the British Interplanetary Society.2953

17.1 Communication vs. Transportation
arthur clarke


There is a  complementary
relationship between
travel and communications:

The better either is, the less
is the need for the other.

Many scientists who might admit the possibility of starflight nevertheless question it on grounds of necessity. Why, they ask, should we or any other sentient race go to the trouble of transporting massive material structures from star to star when information about extraterrestrial intelligences can be gained much more cheaply by listening with radio waves? Indeed, notes Purcell, "a 10-word telegram can be transmitted over a 12 light-year path with a dollar’s worth of electrical energy."

It is well-known that the equations
of Special Relativity (and other
theories too) yield solutions for
particles that go faster than light.

These hypothetical particles,
called "tachyons," have rest masses
represented by "imaginary" numbers.

Since no one could see how objects
with "imaginary mass" could possibly
exist, the solutions were long ignored.
Tachyons

And ET communications might not be limited to the speed of light, either. It is well-known that the equations of Special Relativity (and other theories too*) yield solutions for particles that go faster than light. These hypothetical particles, called "tachyons," have rest masses represented by "imaginary" numbers. Since no one could see how objects with "imaginary mass" could possibly exist, the solutions were long ignored.

Then, in 1962, Drs. O.M.P. Bilaniuk, V.K. Deshpande, and E.C.G. Sudarshan of the University of Rochester in New York reexamined the entire question. In their seminal paper "Meta-Relativity" they pointed out that if tachyons were always in motion, and at speeds perpetually faster than light, it wouldn’t matter what kind of number represented the mass. What really mattered was that tachyonic energy and momentum be "real" — which they are. According to the three physicists:

In classical mechanics the mass is a parameter which cannot be measured directly even for slow particles. Only energy and momentum, by virtue of their conservation in interactions, are measurable, therefore must be real. Thus the imaginary result for the rest mass of the {tachyon} offends only the traditional way of thinking, and not observable physics.1515

In recent times scientists have managed partially to resolve many of the apparent causality violations engendered by faster-than-light tachyons.
(See especially Antippa and Everett,1495,1477 Bilaniuk and Sudarshan,1516,1517 Feinberg,1492 Harwit,1478 Newton,645 Parmentola and Yee)1493 Recami and Mignani,1511 and Trefil.2026) Several experimentalists are now quietly searching for the controversial and elusive particles in what one describes as "a low key effort."646

 Tachyon communication details 

Click for Synopsis   

Normal matter as we know it:

  • When propulsive energy is applied, goes faster

Tachyons, in contrast:

  • Are expected to speed up as they lose energy
  • At zero energy they should have infinite velocity
  • Be present everywhere in the physical universe at the same time
  • (along a Great Circle route)
  • This is called a "transcendental tachyon."

If tachyons exist:

  • Information could be transmitted between stars and even galaxies arbitrarily fast.
  • Any location in the cosmos could remain in direct communicative contact with any other.

With such a perfect means of communication

  • Extraterrestrial races need never leave home and venture out into space.

Conversely, with perfect, instantaneous transportation.

  • Any location in the physical universe can be reached in the blink of an eye.
  • There may be no need for communications at all — it’s quicker just to travel
Transcendental tachyon

Confirmation of the existence of tachyons would have dramatic implications in the field of interstellar communications. Normal matter as we know it, when propulsive energy is applied, goes faster. Tachyons, in contrast, are expected to speed up as they lose energy. At zero energy they should have infinite velocity, and be present everywhere (along a Great Circle route) in the physical universe at the same time. (This is called a "transcendental tachyon.") If tachyons exist, information could be transmitted between stars and even galaxies arbitrarily fast. Any location in the cosmos could remain in direct communicative contact with any other. With such a perfect means of communication, extraterrestrial races need never leave home and venture out into space.

Conversely, let us imagine a civilization with perfect, instantaneous transportation. Any location in the physical universe can be reached in the blink of an eye. In such a society there may be no need for communications at all — it’s quicker just to travel. We see that there is a kind of complementary relationship between travel and communications: The better either is, the less is the need for the other.81

One very critical difference

There is, however, one very critical difference. A single party may engage in travel, but it takes two parties to communicate. If alien societies are to talk, both communicants and recipients must exist. Yet either can launch an interstellar exploratory mission without any knowledge of the other. Furthermore, if extraterrestrial cultures are to communicate, each must make a series of correct assumptions about the motivations, psychologies, and technologies of the others in order to be successful. Interstellar exploration by starship, on the other hand, requires no such ad hoc assumptions to succeed.

There are many other reasons why xenologists have concluded that interstellar travel is the preferred mode for first contact and galactic unification. Communication by radio does not permit contact between an advanced society and one that is intelligent but is not in possession of electronic technology. Such a culture need not necessarily be "unlikely to be of interest to us" as asserted by some radioastronomers. Aliens without radio may have other forms of technology — biological, chemical, social, economic — that would be fascinating to observe and yet do not involve electromagnetic radiation. As Arthur C. Clarke says, only starflight makes it possible "to gain knowledge of star systems which lack garrulous, radio-equipped inhabitants."2731

If alien societies are to talk, both
communicants and recipients must
exist. Yet either can launch an
interstellar exploratory mission
without anyknowledge of the other.
Aliens without radio may have other
forms of technology — social, economic,
biological, chemical — that would be
fascinating to observe and yet do not
involve electromagnetic radiation.

Interstellar travel also would allow:

  • the exchange of artifacts and biological specimens
  • direct observation of a multitude of independent biologies and societies
  • the making of symbolic gestures of sociopolitical and cultural community

The sciences of astronomy and astrophysics would prosper. Direct astronomical samplings could be made of:

  • stars in various stages of evolution
  • distant planetary systems
  • ancient globular clusters
  • interstellar gas clouds

Cooperative scientific ventures could be undertaken with other races, such as performing trigonometric parallax experiments on extremely distant objects. And direct contact is probably the most effective way to achieve a meeting of minds between beings with utterly different histories and ways of thought.1317


* In one mathematical model of particle motion in a special five-dimensional space-time, velocities as high as 1021 times the speed of light appear possible.2893

17.2 Relativistic Starflight  
Consequences of near-lightspeed voyages

So we see that galactic and intergalactic commerce
and tourism are very real possibilities for advanced
extraterrestrial societies.

The dispatch of an interstellar personnel carrier by
a Type II culture, or a high-acceleration intergalactic
cargo transport vehicle by a Type III culture,
represents about the same allocation of energy
and resources as the launching of a Saturn V rocket
by human Type I civilization.

 Light-speed jargon 

Click for Synopsis   

Velocity of light:

  • "optic velocity"
  • Designated as "c"
  • this is a kind of "cosmic speed limit"
  • imposed on all material objects within the physical universe

Other jargon for c includes:

  • "100 psol" or percent-speed-of-light
  • "Mike 1.0" after Dr. Albert A. Michelson

Velocities below c are referred to as:

  • "suboptic"
  • "subluminal"

Velocities faster than light are called:

  • "FTL"
  • "hyperoptic"
  • "superluminal"

Alien and human astronauts alike must conform to the dictates of Relativity when traveling at velocities near the speed of light. Einstein’s theory, generally accepted today by the scientific community, predicts a host of fascinating consequences of near-lightspeed voyages.

First, we should briefly mention some of the jargon commonly employed by physicists and writers in this field. Relativity predicts that no material object can be accelerated up to the speed of light without an expenditure of an infinite amount of energy. Since the entire universe contains only 1081 joules of energy, attaining the speed of light becomes a practical impossibility. The velocity of light, designated as "c", this is a kind of "cosmic speed limit" imposed on all material objects within the physical universe. (Other jargon for c includes "100 psol" or percent-speed-of-light, and "Mike 1.0" after Dr. Albert A. Michelson.) Velocities below c are referred to as "suboptic" or "subluminal"; those faster than light are called "FTL," "hyperoptic" or "superluminal." The speed of light itself is "optic velocity."

Twin Paradox

Now back to the fascinating consequences. According to Relativity theory, time passes more slowly at near-optic velocities than at low suboptic ones. This apparent breach of common sense is traditionally presented in the form of a paradox. Imagine twin brothers A and B. A becomes an astronaut and flies away in a relativistic starcraft capable of a peak velocity of 98%c. B stays behind on Earth. A travels 12 light-years out into space, and then 12 light-years back to Earth. Because A has been moving slower than light, B must wait a total of 28 years for his return. B is thus 28 years older than his age when the brothers parted. But when he meets A in the Debarkation Area, A has only aged 10 years. A is 18 years younger than his identical twin.

This unusual consequence of near-optic flight, often called the Twin Paradox, has been confirmed indirectly by scores of experiments over the past half-century. There is little doubt in the minds of most physicists that the Paradox is a correct prediction of the consequences of traveling close to the speed of light. The contraction of time at high velocities is known as the phenomenon of time dilation.

Effective FTL starflight using relativity theory

Table 17.1 Effective FTL Starflight Using Relativity Theory

table 17 1 effective f t l starflight 400
An astronaut, provided his starcraft has
sufficient energy, can effectively travel
faster than the speed of light relative
to a stationary frame of reference!

The frame of reference of the observer is of critical significance here. Those observers who remain at rest with respect to the universe at large (such as the twin who stays on Earth) will always observe a relativistic starcraft to travel at suboptic velocities. But to the astronauts on board the spaceship, the contraction of distance between the points of origin and destination (another peculiar consequence of Relativity theory) will make the trip seem shorter. They will, from their frame of reference, actually be moving at a faster apparent velocity than that perceived by stationary observers (say, back on Earth). In fact, when the starship reaches exactly 70.7%c as measured by stationary observers, the astronauts calculate their own effective velocity as 100%c! As acceleration continues still further, shipboard-determined speed increases to seemingly hyperoptic velocities (which Earthbound observers still see as suboptic from their frame of reference).

Time dilation

Table 17.2 Duration of Interstellar Travels, Using

a Standard Flight Plan at One Gee Acceleration

table 17 2 duration of interstellar travels 350

 The Standard Flight Plan 

Click for Synopsis   

The Standard Flight Plan


  • Uniform acceleration from start point to the midpoint of trip
  • Uniform deceleration from midpoint of trip to destination
  • Same rate of change in velocity for both legs

What does all this mean in plain English? Simply this: An astronaut, provided his starcraft has sufficient energy, can effectively travel faster than the speed of light relative to a stationary frame of reference! (See Table 17.1 for details.)

With 1 gee acceleration

Ship-time required for voyage:


  • Few years to the nearest stars
  • 21 years to the Galactic Core
  • 28 years to Galaxy Andromeda
  • (effective velocity of 61,000 × c ) 

Time dilation permits very long journeys within a single human lifetime. Consider a starship that accelerates uniformly to the midpoint of the trip and then decelerates uniformly at the same rate the rest of the way to the destination — called the Standard Flight Plan. With an acceleration of 1 gee — appropriate for inhabitants of terrestrial worlds similar to Earth — only a few years of ship-time are required to reach the nearest stars. (See Table 17.2.) Only 21 years are spent reaching the Galactic Core, and in 28 years of shipboard time the intrepid explorers can visit Galaxy Andromeda in person. Since Andromeda is about 1.7 million light-years distant, this works out to a mean effective velocity of 61,000 times the speed of light.

Twin Paradox with a vengeance!

Of course, there is no time dilation on the home planet — since it went nowhere. If our intergalactic astronauts turned around at Andromeda and immediately returned to Earth, they would have aged a total of 56 years. The Earth and all of its inhabitants, however, would have aged 3.4 million years. This is a "twin paradox" with a vengeance!

Starship acceleration

Table 17.3 Acceleration Required to Complete Journey in

One Decade Shipboard Time, Using Standard Flight Plan

table 17 3 acceleration required to complete journey 400

Relativity does permit effectively
hyperoptic interstellar journeying.

When science fiction writers and others speak of "FTL" they are usually referring to true (rather than "effective") FTL — that is, faster-than-light travel from the point of view of both astronauts and stay-at-homers. We shall discuss the theoretical possibility of true FTL later in this chapter. But for now it is important only to realize that Relativity does permit effectively hyperoptic interstellar journeying, at least from the standpoint of an astronaut setting forth to explore the universe.

This fact is highlighted by the data shown in Table 17.3. It is assumed that an astronaut wishes to travel a certain distance out into space, but he doesn’t want to use up more than 10 years of his life in getting there. Table 17.3 lists the starship accelerations that must be sustained throughout the entire trip in order to arrive at a destination at the specified distance within exactly one decade as measured on the astronaut’s own wristwatch. A Standard Flight Plan is assumed.

The levels of power expenditure needed
to achieve the benefits of relativistic time
dilation are enormous by today’s standards.

Note that any point in our Milky Way galaxy can be reached in ten years of shipboard time, at accelerations tolerable to human beings for long periods of time. Accelerations of 2-4 gees, perhaps sustainable by inhabitants of jovian or heavy subjovian worlds, or by bioneered former inhabitants of terrestrial worlds, would put the entire known universe within 10 years reach.

Naturally, the faster a starship is pushed the more energy is required. The levels of power expenditure needed to achieve the benefits of relativistic time dilation are enormous by today’s standards, even for fairly small vehicles. (See Table 17.1.) But as we shall see presently, this by no means bars interstellar or intergalactic commerce. Indeed, such commerce should be commonplace among Type II and Type III civilizations.

Three classes of starflight missions

Let us consider three illustrative classes of starflight missions:

  • 1. Interstellar personnel transport;
  • 2. Intergalactic personnel transport;
  • 3. Intergalactic cargo transport.
Big and costly

Too many writers have succumbed to the Fallacy of the Big and the Costly. That is, if it’s big and it costs a lot, it must be impossible. The Fallacy lies in the simple observation that what seems big and costly to one culture may be negligible and cheap to another.

 Relative energy costs (REC)  
  of Saturn V rocket booster  

Click for Synopsis   

The Saturn V rocket booster

  • Developed 1.3 × 1011 watts of power for about 150 seconds
  • Equivalent of harnessing the entire human energy output for exactly 4 seconds

One Saturn V equals 4 seconds of humanity’s aggregate power output

Saturn V rocket

The relative costs of missions to the stars may perhaps best be appreciated by a comparison with the familiar. Humanity has launched about ten Saturn V rocket boosters to date. Each of these blustering behemoths developed 1.3 × 1011 watts of power for about 150 seconds each. This is the equivalent of harnessing the entire human energy output for exactly 4 seconds. Keep this quantity in mind as we work through the following examples: One Saturn V equals 4 seconds of humanity’s aggregate power output.

 REC of interstellar personnel transport 

Click for Synopsis   

Relative energy costs of interstellar personnel transport

  • Assume a Standard Flight Plan at a constant 1 gee acceleration
  • Assume a flight distance of 100 light-years
  • Total trip time works out to 9 years.

How much energy is required?

  • Mass of the vessel equals the Starship Enterprise (190,000 metric tons)
  • About 9 × 1026 joules of energy are required for the mission

Mature Type II civilization

  • 1026 watts (joules/sec) at its disposal
  • Mission uses nine seconds of culture’s total power output

Single interstellar personnel transport mission
equivalent to launching two Saturn V rockets



For a Type III civilization this mission is inordinately trivial

  • 44 billion such starliner missions could be dispatched
  • Uses 4 seconds of galactic society’s aggregate energy output

44 billion missions comparable to launching of a single Saturn V

Interstellar personnel transport

First we consider the interstellar personnel transport mission. We assume a flight distance of 100 light-years, appropriate for short hops between neighboring Type II civilizations. To make things comfortable for the pilots and passengers, we further assume a Standard Flight Plan at a constant 1 gee acceleration. Using the equations of Special Relativity, total trip time works out to a mere 9 years.

How much energy is required? If we take the mass of the vessel to equal that of the Starship Enterprise of original-series Star Trek fame (190,000 metric tons), then about 9 × 1026 joules of energy are required for the mission. A mature Type II civilization, having 1026 watts (joules/sec) at its disposal, should have no trouble with this at all. The interstellar personnel transport mission uses only nine seconds of the culture’s total power output, a feat equivalent in stature to the launching of two Saturn V rockets by modern human engineers. For a Type III civilization, this mission is inordinately trivial. In fact, roughly 44 billion such starliner missions could be dispatched if only 4 seconds of the galactic society’s aggregate energy output were utilized — a feat comparable to the launching of a single Saturn V from Earth today.

 REC of intergalactic personnel transport 

Click for Synopsis   

Relative energy costs of intergalactic personnel transport

  • Assume a Standard Flight Plan at a constant 1 gee acceleration
  • Assume a flight distance of 1.7 million light-years to Galaxy Andromeda
  • Total trip time is 28 years

How much energy is required?

  • About 1.5 × 1031 joules of energy are required for the mission

Mission would tax the resources of Type II culture to the breaking point

  • Mission uses 41 hours of culture’s total power output

Single intergalactic personnel transport mission
Analogous to the firing of 38,000 Saturn V’s



Mature Type III civilization

  • 1037 watts (joules/sec) under its control this mission is utterly trivial
  • 2.5 million missions could be dispatched to Galaxy Andromeda
  • All 2.5 million missions equal 4 seconds of culture’s total power output

2.5 million missions comparable to launching of a single Saturn V

Intergalactic personnel transport

What about our second class of starflight mission — the intergalactic personnel transport? These are somewhat more difficult, probably well out of reach of a lone Type II civilization. Again, using a Standard Flight Plan at 1 gee acceleration to keep crew and passengers at ease, a trip of 1.7 million light-years to Galaxy Andromeda (the nearest giant spiral) would require only 28 years shipboard time. Approximately 1.5 × 1031 joules would be consumed making the journey.

Such a mission would tax the resources of Type II culture to the breaking point. More than 41 hours of the stellar society’s power output would be needed to launch a single intergalactic starliner, a feat analogous to the firing of 38,000 Saturn V’s by present-day humankind. Such an enormous sacrifice and commitment of resources would require some overwhelmingly compelling purpose to justify it.

For a mature Type III galactic civilization with 1037 watts under its control, however, the intergalactic personnel transport mission would again prove utterly trivial. Such a culture could launch more than 2.5 million such sorties to Galaxy Andromeda for a mere 4 seconds worth of its total power output — again, a feat comparable to our launching a single Saturn V rocket.

 REC of intergalactic cargo transport 

Click for Synopsis   

Relative energy costs of intergalactic cargo transport

These ships can be unmanned. Far higher accelerations may be tolerable

  • Assume a Standard Flight Plan at 106 gees acceleration
  • (probably the upper limit for normal physical materials)
  • Assume a flight distance of 1.7 million light-years to Galaxy Andromeda
  • Assume a robot-controlled, 190,000-metric-ton cargo ship
  • Shipboard time of flight is only 1724 seconds (a bit under half an hour)
  • Ship and contents subjected to extreme forces only briefly

How much energy is required?

  • Total of 1.5 × 1037 joules of energy are required for the mission
  • Mission uses 1½ seconds of aggregate power output of a galactic culture

For a Type III civilization

  • Launching two high-acceleration cargo vessels
  • Equivalent to launching one Saturn V
Intergalactic cargo transport

Finally, we consider the case of the intergalactic cargo transport mission. Since these ships can be unmanned, far higher accelerations may be tolerable. We assume a robot-controlled, 190,000-metric-ton cargo ship, dispatched to Andromeda at an acceleration of 106 gees (probably the upper limit for normal physical materials) on a Standard Flight Plan. Fortunately, the shipboard time of flight is only 1724 seconds, a bit under half an hour, so the ship and its contents are subject to extreme forces only for a very brief period of time. A total of 1.5 × 1037 joules are required for the mission, about 1½ seconds of the aggregate power output of a galactic culture. To a Type III civilization, the launching of two such high-acceleration cargo vessels requires a resource commitment equivalent to the launching of one Saturn V by human technologists.

So we see that galactic and intergalactic commerce and tourism are very real possibilities for advanced extraterrestrial societies. The dispatch of an interstellar personnel carrier by a Type II culture, or a high-acceleration intergalactic cargo transport vehicle by a Type III culture, represents about the same allocation of energy and resources as the launching of a Saturn V rocket by human Type I civilization.

17.3 Conventional Interstellar Propulsion Systems
17.30 Conventional Interstellar Propulsion Systems

robert heinlein

Requirements for starflight:


  • First, the kinematics must be right
  • Second, sufficient available energy
  • Third, astronautic technology exists
  • (capable of performing the requisite
  • kinematics using the available energy)

Three fundamental requirements must be satisfied if starflight is to be considered plausible for alien or human civilizations. First, the kinematics must be right. Second, the energy available for the mission must be sufficient. Third, there must exist an astronautic technology capable of performing the requisite kinematics using the available energy. In the preceding section we saw that the kinematic and energetic requirements are satisfied by Type II and Type III civilizations operating within the bounds of Einsteinian Relativity theory. For the remainder of this chapter the third requirement is examined in more detail — the technological aspects of interstellar voyaging.

Four stages of technical progress
Matching this progression against current human
achievements, we find that radio, television,
computers, automobiles, and chemical rockets all
have arrived at the profit stage here on Earth.

Advanced technologies as nuclear power planets,
SSTs, and fission propulsion rockets are at the
practice stage, awaiting full societal and economic
commitment to move them into the profit stage.

Laser fusion and satellite solar power stations
are presently in transition from theory to practice.

Consider the nature of technical progress. There is an orderly progression from the emergence of new ideas, further research and development, then finally a reduction to practice and economic exploitation. Thus, the realization of new technology normally proceeds in four stages:

  • Stage 1 — IDEA — the basic philosophical idea, discovery of a new physical law, a new branch of mathematics, a new possibility within the existing framework of science.
    (See Hogan2916 for an excellent example of this in science fiction.)
  • Stage 2 — THEORY — development of the mathematical/physical theoretical framework which ties the new idea to other known phenomena.
  • Stage 3 — PRACTICE — research and engineering; building a device which utilizes the new idea in its manufacture or operation.
  • Stage 4 — PROFIT — social, political, and economic acceptance and exploitation; who pays for it, is it worth the effort, who will benefit, etc.?

Matching this progression against current human achievements, we find that radio, television, computers, automobiles, and chemical rockets all have arrived at the profit stage here on Earth. Such advanced technologies as nuclear power planets, SSTs, and fission propulsion rockets are at the practice stage, awaiting full societal and economic commitment to move them into the profit stage. Laser fusion and satellite solar power stations are presently in transition from theory to practice.

The five conventional interstellar propulsion systems described in this section are all at the theory stage in human technological development. Each has received sufficient study to tell us that they have the basic physical and energetic feasibility to be considered for missions to the stars. All retain a number of technical uncertainties which will require significant engineering effort to overcome. Nevertheless, xenologists expect that all five propulsion systems are likely to advance at least to the practice stage within a century or less on this planet. So it is likely that these same systems also accurately represent the interstellar transport technologies of many extraterrestrial sentient races in the universe.

A sixth conventional interstellar propulsion system employing paired high-energy mass drivers for efficiently transporting massive cargoes between distant stars is briefly described in Section 21.4.1.

17.3.1 Nuclear Pulse Propulsion

Figure 17.1 Project Orion (from Dyson478)

figure 17 1 project orion 350

Figure 17.2 Nuclear Pulse Vehicle

(from Forward718,2812)

figure 17 2a nuclear pulse vehicle 350
figure 17 2b nuclear pulse vehicle 350

 Nuclear pulse vehicle 

Click for Synopsis   

Dyson’s nuclear pulse vehicle

  • 400,000-ton craft is propelled up to 3.3%c
  • Final velocity of 10,000 km/sec
  • Exhausts its bomb supply in ten days

For a simple flyby mission

  • Flight time to Proxima Centauri in 130 years

For an encounter-capture mission

  • Payload must be decelerated at the target
  • More than doubles the time of flight


Daedalus system

  • 54,000-ton craft is propelled up to 12%c
  • Probe to Proxima Centauri in 35 years with a 500-ton payload

In the 19th century Hermann Ganswindt proposed the use of a series of gun powder charges behind a vessel to propel it into space.2762 The concept of nuclear pulse propulsion, the modern extension of this basic idea, was developed under USAF contract at Gulf General Atomic during the years 1958-1965.

Project Orion

Consists of five distinct parts:


  • Hemispheric ablation shield
  • (or "pusher plate")
  • Enormous shock absorber
  • Bomb ejection mechanism
  • The bomb magazine
  • Payload at the front end
Project Orion

Dubbed "Project Orion" by the scientists who worked on it, the system operates by tossing out a nuclear bomb, exploding it astern of the ship, and absorbing part of the momentum of the resulting debris. The rocket thus consists of at least five distinct parts: An hemispheric ablation shield or "pusher plate," an enormous shock absorber, a mechanism for ejecting the bombs, the bomb magazine, and finally the payload at the front end. Small test models using steel pusher plates and TNT charges were successfully flown during the experimental phase of Project Orion, but the work was shelved after the Nuclear Test Ban Treaty entered into force late in 1963. (The Treaty prohibits the explosion of nuclear devices in the atmosphere or in space.)

Freeman J. Dyson of the Institute for Advanced Study at Princeton, New Jersey, who worked on Project Orion, described a prototype model of a space vehicle utilizing the principle of nuclear pulse propulsion.476 His "Ablation Space Ship" has a total mass of 400,000 metric tons, consisting of 300,000 tons of one-megaton H-bombs (weighing 1000 kg each), 50,000 tons of structure and payload, and 50,000 tons of ablation shield. The pusher plate construction is such that about 30 meters/second forward velocity are imparted to the vessel with each explosion. A smooth 1-gee acceleration is maintained by the detonation of one bomb every three seconds, which requires a shock absorber stroke length of about 75 meters (Figure 17.1).

Dyson’s nuclear pulse vehicle exhausts its bomb supply in ten days, having reached a final velocity of 10,000 km/sec (about 3.3%c). The flight time from Earth to Proxima Centauri would then be 130 years for a simple flyby mission. For an encounter-capture mission the payload must be decelerated at the target, which more than doubles the time of flight for a vehicle of this size.

Daedalus starprobe

More efficient variants of the nuclear pulse technique have been suggested in recent times (Figure 17.2), particularly the idea of igniting tiny deuterium pellets instead of huge bombs behind the ship. Ignition would be achieved using pulsed laser beam fusion2751,2752 or heavy ion or electron beam fusion.2764 This latter technique has been selected for use in the Daedalus starprobe, an interstellar vehicle designed as part of a feasibility study sponsored by the British Interplanetary Society during 1975-1977.2953 In the Daedalus system, a 54,000-ton craft is propelled up to 12%c using a stream of frozen deuterium/helium-3 pellets which are zapped by a megavolt electron gun 250 times a second. The designers claim that the probe should be able to reach Proxima Centauri in 35 years with a 500-ton payload.2761

17.3.2 Controlled Fusion Rocket

Montage of fusion-powered interplanetary

spacecraft concepts from 1987-2004 (from Wikipedia)

fusion powered montage interplanetary spacecraft 1987 2004 400

Theoretically, a fusion-powered
starship could be fueled by
hydrogen isotopes drained from
the atmosphere of Jupiter or
from the icy rings of Saturn.

Another highly promising starship propulsion system is the technique of using a controlled, continuous thermonuclear fusion reaction as the main power source. Because of the tremendous temperatures involved (upwards of 10,000,000 K), no known material can physically contain a fusion reaction. Magnetic fields therefore must be used to contain, compress, and heat the plasma fusion fuel (hydrogen, deuterium, tritium, etc.). Scientists are currently engaged in designing and testing various "magnetic bottle" configurations strong enough to hold such an energetic plasma, in connection with electrical power generation at major fusion research facilities around the world.

Magnetic bottle

The biggest problem is to make the magnetic bottle leakproof enough so that fusion reactions occur in sufficient abundance for the process to become self-sustaining. In terms of propulsion, however, a leaky bottle is exactly what is required. Hot plasma, energized by fusion energy, streams rapidly from the site of the "leak" and produces the desired rocket thrust.

According to Dr. Robert L. Forward, Senior Scientist at Hughes Research Laboratories, a deuterium fusion rocket capable of a steady 1-gee acceleration and consisting 90% of fuel (by mass) could reach a final velocity of 10%c.718 This would mean a travel time to Proxima Centauri of 45 years. Theoretically, a fusion-powered starship could be fueled by hydrogen isotopes drained from the atmosphere of Jupiter or from the icy rings of Saturn, and writer Alan Bond has estimated that a 10 light-year mission could be completed in 60 years.1159

One major problem to be overcome from
a practical standpoint is to learn how to
deal with the various forms of energy
released by a fusion engine. …

the lion’s share (70%) is released as X-rays.
Waste X-rays

One major problem to be overcome from a practical standpoint is to learn how to deal with the various forms of energy released by a fusion engine. Only about 20% of the energy liberated by nuclear reactions appears as kinetic energy — direct propulsive thrust — in the leaking plasma stream. Ten percent is thrown off as heat and ultraviolet radiation, but the lion’s share (70%) is released as X-rays. G.L. Matloff and H.H. Chiu have suggested that this energy may be reclaimed by using an auxiliary laser thruster surrounding the fusion reaction chamber.2754 Waste X-rays, absorbed by, say, xenon-doped gas in the laser, are converted into a collimated light beam which serves as a photon thruster.*


Futuristic propulsive energy systems

* A wide variety of related but "futuristic" propulsive energy systems may be possible. These may include:

  • Condensed cold neutron reactions
  • Pion fusion (which has been demonstrated experimentally)
  • Muon catalysis fusion,2737
  • Hawking black hole induced fusion1947
  • Compact monopole fusor and energy storage devices or magnetic monopole metamatter.1224
  • Fission rockets are not ruled out2758
  • High-energy superpropellants such as monatomic hydrogen, metallic hydrogen,2684 cryogenic metastable triplet helium (stores 0.5 megajoule/gram) may be available.2736
17.3.3 Interstellar Ramjet

Figure 17.3 Bussard Interstellar Ramjet2812

figure 17 3a bussard interstellar ramjet 350
figure 17 3b bussard interstellar ramjet 350
The Bussard ramjet is perhaps the
most intensively scrutinized potential
interstellar propulsion system.

The interstellar ramjet, first proposed by Dr. Robert W. Bussard at Los Alamos Scientific Laboratory in 1960, is a propulsion system which acquires energy and reaction mass from the surrounding medium.2766 Using some combination of electric and magnetic fields, the ramjet scoops up ionized interstellar gases to fuel its fusion rockets. This eliminates the need to carry large masses of fuel on board. Conventional chemical or nuclear rockets must be used to accelerate the starrammer up to about l-5%c, the threshold velocity at which the ramscoop mechanism becomes reasonably efficient.

The forward scoop would be immense (Figure 17.3). Bussard originally calculated that a 1000-ton vehicle would require a funnel diameter of 3600 kilometers to achieve a one-gee acceleration in normal interstellar space (~1 H-atom/cm3). In regions of dense hydrogen clouds, with perhaps 103 atoms/cm3, the ramscoop diameter could be as small as 120 kilometers. Theoretically, the acceleration could be maintained indefinitely, making possible the circumnavigation of the entire universe in less than a human lifetime.2755

Such monstrous scoops, of course, need not be constructed of physical materials. Most probably electromagnetic fields will suffice. To generate such fields, A.J. Fennelly of Yeshiva University and G.L. Matloff of the Polytechnic Institute of New York proposed in 1974 an annular copper cylinder coated with a layer of superconducting tin-niobium alloy (Nb3Sn).1454 The device would be rather modest in size (as starships go), measuring 400 meters in length and 800 meters in diameter. Energized with electrical current, an electromagnetic scoop with an effective diameter of 10kilometers would be generated. For braking at the destination, a drogue chute made of boron (noted for its high melting point) about 10 km in diameter is recommended. (An electrically charged wire mesh would give sufficient drag without being destroyed by erosion.1066,1061)

As if to underscore the tremendous engineering difficulties involved in scoop design, Fennelly and Matloff announced in 1976 their original device was simplistic and probably would not work:

It is not possible, we have found, to design such a scoop. The {forces} induced … stress a scoop beyond the elastic limit of the substrate material and shear the superconductor to such an extent that it will be driven to a normally resistive state, with a subsequent catastrophe from the almost instantaneous Joule heating.1615

Nevertheless, assert the authors gamely, "we have hope that further analysis will lead to feasible scoop designs with some type of electromagnetic field to give a large scoop effective radius." It is now believed that a mixed electrostatic/electromagnetic field design will give the best results. (See Matloff,2759 Matloff and Fennelly,2766 and Powell.2760)

As if to underscore the tremendous
engineering difficulties involved in
scoop design, Fennelly and Matloff
announced in 1976 their original
device was simplistic and
probably would not work.

By adding "wings" to the starrammer, travel times may be cut in half.2782 Explains one writer:

The wings are two great superconducting batteries, each a kilometer square. Cutting the lines of the galactic magnetic field, they generate voltages which can be tapped for exhaust acceleration, for magnetic bottle containers for the power reaction, and for inboard electricity. With thrust shut off, they act as auxiliary brakes, much shortening the deceleration period. When power is drawn at different rates on either side, they provide maneuverability — majestically slow, but sufficient — almost as if they were huge oars.2180

Collateral design and operational problems

The Bussard ramjet is perhaps the most intensively scrutinized potential interstellar propulsion system. As a result, scientists are beginning to call attention to collateral problems involved in the design and operation of ramscoop vehicles.1155 One objection voiced by John Fishback in 1969 is fundamental.1461 He points out that the section of the starship which contains the sources of the magnetic scoop fields must be strong enough to withstand the forces generated by those fields. As the starcraft goes faster and faster, the required field strengths also increase. Since materials are limited by their maximum tensile strength, at some point the acceleration of the vehicle will have to be reduced to avoid the breakdown of its structure caused by the pressure of magnetic forces.1462

For realistic building materials, this cut-off velocity at which further acceleration must be drastically curtailed occurs at about 99.999998%c. This is high enough to be of no practical significance for galactic travel at 1 gee, but may prove restrictive for higher acceleration rammers or for starships on intergalactic missions.

Micron-sized frozen deuterium pellets
are accelerated electrostatically or
electromagnetically out into space several
years prior to the launching of a standard
Bussard ramjet having a comparatively
small scoop cross-section (perhaps it
would be just a simple physical structure,
such as a giant funnel).

The starrammer could then collect a more
concentrated fuel en route simply
by staying on the "runway."
Finicky hydrogen

Another major difficulty, noted by Bussard and many others since, is that the proton-proton nuclear reaction is a poor candidate for fusion rockets. Most of the gas likely to be scooped up by the interstellar ramjet will be ordinary hydrogen, and hydrogen is very finicky when it comes to fusion. Deuterium reactions have a cross-section roughly twenty orders of magnitude greater, but this heavy isotope of hydrogen is relatively rare in the interstellar medium.

Catalytic nuclear ramjet

Recently, Daniel P. Whitmire has suggested the concept of a catalytic nuclear ramjet to overcome this problem.1471 In Whitmire’s scheme, the starship would carry on board a supply of "nuclear catalyst" consisting of carbon, nitrogen, and oxygen atoms. This fuel additive should catalyze a vastly increased reaction rate among ordinary hydrogen atoms without itself being consumed. Calculations indicate that this technique will yield a rate of fusion more reasonable from the standpoint of interstellar missions. For this scheme to succeed, of course, a workable heavy ion fusion reactor must be developed, but, in Whitmire’s words, "the difficulty seems to be of a technological rather than fundamental nature." (He also proposes the use of a bank of forward lasers to ionize neutral atoms approaching the rammer’s maw, thus greatly increasing the reaction mass available for the starship’s engines.)

Ram Augmented Interstellar Ramjet

An interesting hybrid variation of the basic ramscoop technique involves a vessel that carries its own nuclear fuel supply and exhausts the reaction products for thrust, much like a conventional fusion rocket. However, this Ram Augmented Interstellar Ramjet, or RAIR as Alan Bond of the British Aircraft Corporation calls his device, enhances its performance by scooping up atoms from the interstellar medium and using them as reaction mass rather than for energy generation.1455

In other words, fusion fuel is carried by the spaceship and additional reaction mass is collected from gas clouds through which the vessel passes. Preliminary calculations show that the RAIR design may save at least an order of magnitude of fuel savings at speeds up to 50%c, and as much as two orders of magnitude of fuel savings up to 70%c. Performance characteristics of RAIR starships have been worked out by Bond1455 and Powell.1117,1115,2769

Fusion Ramjet Runway

Two other fascinating variations on the interstellar ramjet have been proposed by Whitmire and A.A. Jackson IV.2733 The first of these is called the Fusion Ramjet Runway. Micron-sized frozen deuterium pellets are accelerated electrostatically or electromagnetically out into space several years prior to the launching of a standard Bussard ramjet having a comparatively small scoop cross-section (perhaps it would be just a simple physical structure, such as a giant funnel). The starrammer could then collect a more concentrated fuel en route simply by staying on the "runway."

Stellar Ramjet

The other suggestion, rather bizarre and considerably less likely, is the Stellar Ramjet. This vehicle accelerates up to near-optic velocity across the photosphere of a star. Whitmire and Jackson propose that the envelope of a red giant or a large protostar would be ideal for this technique. Accelerative forces would be large but not prohibitive, and biological crews should survive if they are somehow immobilized or "frozen" during the starship’s relatively brief period of acceleration.

17.3.4 Beamed Power Laser Propulsion

Figure 17.4a Beamed Power Propulsion Laser-Pushed Vehicle718

figure 17 4a beamed power propulsion laser pushed vehicle 350

Figure 17.4b Beamed Power Propulsion Laser-Pushed Vehicle718

figure 17 4b beamed power propulsion laser pushed vehicle 350

It may be best to use an
external source of energy
to achieve near-optic speeds.

We have seen that it may be best to use an external source of energy to achieve near-optic speeds. The interstellar ramjet discussed above is a good example of this technique. Another possibility is the Laser Pushed Vehicle, or LPV.122,2767

The LPV obtains its energy and momentum from a solar-system-based laser network which pushes the ship by photon reflection from an onboard mirror. Calculations indicate that a power of roughly 1014 watts delivered to a 100-ton starship should be sufficient to impart a one-gee acceleration to the craft. Focusing would be of critical importance, and it may turn out that only x-rays will have a small enough wavelength/diameter ratio to forestall gross energy wastage. Upon arrival at a destination, LPV deceleration is effected in reverse fashion with the active assistance of the receiving civilization.22

What if there is no receiving civilization? Is the Laser Pushed Vehicle strictly limited to one-way flyby missions of exploration? The answer, apparently, is no.

According to Philip Norem, a space-based laser system could be used to accelerate a starprobe up to relativistic velocities. After a while, the craft extends long wires and charges them up to high voltage. These would interact with the Galactic magnetic field, swinging the LPV around in a slow, giant arc (Figure 17.4a). The course is chosen to aim back through the target star system, but on a general heading towards Earth. The wires are discharged and reeled in; the orbital laser network is turned on again, this time functioning to decelerate the starcraft.2756

Very large space-based laser arrays would be required to carry out such a mission, perhaps as big as 250 kilometers in diameter. These should be parked in close solar orbit, drawing their power directly from the high solar flux available there. For maximum efficiency, the LPV’s mirrored "sail" should be of a size comparable to that of the laser array — perhaps 250 km wide, weighing thousands of tons even if it is very thin. Surprisingly, the laser array energy flux need not be very high to push a vehicle to relativistic speeds. Typically the beam should be no more powerful than ordinary sunlight.

Laser Powered Ramjet

A proposed hybrid system combines the best qualities of the interstellar ramjet and the laser pushed vehicle and avoids many of their disadvantages. Called the Laser Powered Ramjet, or LPR, the starcraft obtains its power from a space-based laser network and its reaction mass from the interstellar medium using an electromagnetic ramscoop. The propulsion system is greatly simplified because the LPR does not require an onboard hydrogen-burning fusion reactor motor — since all power is furnished by laser beam. Calculations suggests that the LPR may be superior to the LPV under virtually all conditions. It should also outperform the Bussard ramjet at speeds below 14%c during the acceleration phase and
at all speeds during the deceleration phase of the mission.2733

The starcraft obtains its power from a space-based
laser network and its reaction mass from the interstellar
medium using an electromagnetic ramscoop.

The propulsion system is greatly simplified because the LPR
does not require an onboard hydrogen-burning fusion
reactor motor — since all power is furnished by laser beam.

Calculations suggests that the LPR may be superior to
the LPV under virtually all conditions. It should also
outperform the Bussard ramjet at speeds below 14%c
during he acceleration phase and at all speeds during
the deceleration phase of the mission.
Laser Powered Rocket

Whitmire and Jackson propose two additional alternative propulsion systems that appear promising. The first of these is the Laser Powered Rocket, which differs from the LPR because it carries along its own reaction mass onboard instead of gathering it from the interstellar medium. Extraordinary energy efficiency may be possible because the exhaust velocity is controllable.2733

Particle Powered Ramjet

The second possibility may be called the Particle Powered Ramjet, which obtains its reaction mass, its fuel, or both from space-based particle accelerators: After acceleration, the particles could be neutralized by the addition of electrons or positrons to avoid coulomb spreading of the beam. The neutral particle current required would be relatively modest — for antimatter, about 105 amps to produce 1014 watts on board at low velocities. The problem seems to be collimation since there is no particle analogue to the laser.2733

17.3.5 Total Conversion Drives

Table 17.4 Black Hole Power Generation and

the Spontaneous Evaporation of Hawking Black Holes

table 17 4 black hole power generation 350
Bring together equal quantities
of matter and antimatter, allow
annihilation or "total conversion"
to take place, and then convert
the products to useful thrust.
Antimatter propulsion

The basic idea of using antimatter to power starships has been discussed in the technical and fictional literature for many decades. The most common system is the "photon drive"*: Simply bring together equal quantities of matter and antimatter, allow annihilation or "total conversion" to take place, and then convert the products to useful thrust. Gamma rays as well as high energy electrons and positrons are thrown off, but about half of the energy liberated is in the form of neutrinos which escape isotropically and are wasted.

The usual antimatter propulsion scheme thus amounts to no more than "partial conversion" with an efficiency well below 50%. Better results may perhaps be obtained by using cold or "frozen" positronium gas as fuel. Positronium consists of pseudo-atoms in which a negatively charged electron orbits a positively charged positron (the electron’s antiparticle) — this has been observed experimentally. As the fuel is warmed, electron and positron annihilate, producing a pure beam of gamma radiation. Eugene Sänger proposes using an electron gas reflector to focus and direct the photonic jet.2840 Alan Bond estimates that a million-ton starship with a mass ratio (fueled/unfueled, by weight) of 7.4 and an acceleration of one gee could reach 60%c.1159

The Hawking Black Hole becomes a total
conversion engine when we start "feeding" it.

Evaporation can be indefinitely postponed
simply by shoveling in raw matter — any
matter — at an appropriate rate.

Such a device could be used to construct
an extremely high-efficiency photon drive
propulsive system.

The main problem is how to construct
an HBH in the first place.

Dr. D.D. Papailiou at Jet Propulsion Laboratory in Pasadena claims that for missions to nearby stars optic exhaust velocities are not necessary. A far more efficient technique is to use a small amount of antimatter to energize a large amount of ordinary matter. Preliminary calculations by Papailiou show that a mass ratio of 5.0 and a 2% charge of antimatter (by weight) is optimal to achieve a probe coast velocity of 33%c.2757

So if we wanted to launch a 10-ton starship on an encounter-capture mission, we must built a top stage of 51 tons — the 10-ton probe, 40 tons of ordinary matter, and 1 ton of antimatter — to obtain a mass ratio of 5. This stage serves to decelerate the probe at its destination. To get it there, we will need a 205-ton bottom stage — 200 tons of ordinary matter and 5 tons of antimatter — in order to accelerate the top stage up to 33%c. Delivery of a 10-ton space probe with a coasting speed of 33%c to another star system thus requires a total ship mass of about 256 tons, of which 6 tons are antimatter.

Antimatter Ramjet

A related scheme is the Antimatter Ramjet, which gathers normal matter in the forward scoop primarily as reaction mass. In a manner similar to Papailiou’s antimatter drive outlined above, interstellar matter would be commingled with bits of antimatter stored onboard. In this case the probe need only carry the requisite 6 tons of antimatter fuel when it leaves the planet of origin (perhaps stored in the form of frozen antihydrogen maintained a few degrees above absolute zero), and can pick up the remaining 240 tons of ordinary matter en route to its destination.

Many physicists object to the feasibility of total conversion drives such as those mentioned above because of the difficulty today of generating macroscopic quantities of antimatter. But the problems of creation and control should not prove insuperable. Writes Dr. Forward:

The present methods for producing antimatter involve the use of large accelerators which can produce a proton beam of 1015 protons per second. When such a beam collides with a target, antiprotons are produced as part of the debris. The antiproton yield of present machines is very low. However, the presently used methods are not designed for antimatter production but rather for studies in the physics of elementary particles. Rough calculations assuming special purpose high amperage colliding beam accelerators indicate that the generation of kilograms of antimatter per year is not out of the question. The containment and control of the antimatter, once made, should not be too difficult since we have a number of ways of applying forces to the antimatter without touching it. Electric fields, magnetic fields, rf fields and laser beams are all used in present day technology to levitate and control small amounts of regular matter that we do not want to contaminate. These would all be equally effective on antimatter.718

Hawking Black Holes

Another considerably more speculative total conversion system involves so-called Hawking Black Holes (HBHs). According to Dr. Stephen H. Hawking at the University of Cambridge, all black holes (if any exist) radiate energy due to quantum mechanical "tunneling" effects. This is equivalent to mass loss, so eventually the entire corpus of the black hole "evaporates." A stellar-mass BH is very "cold" — in fact, close to absolute zero — but a low-mass HBH is extremely "hot" and prone to explosive evaporation.2021 For instance, a million-ton HBH should radiate about 1018 watts at a temperature of about 1015 K, and will take about one year to finish evaporating.

The HBH becomes a total conversion engine when we start "feeding" it. Evaporation can be indefinitely postponed simply by shoveling in raw matter — any matter — at an appropriate rate (Table 17.4). Such a device could be used to construct an extremely high-efficiency photon drive propulsive system. The main problem is how to construct an HBH in the first place. Dr. John A. Wheeler estimates that a black hole of mass 10kilograms might be generated artificially by the controlled thermonuclear fusion implosion of approximately 5 × 1013 kg of deuterium.2022 This involves the handling of some 5 × 1028 joules of energy, which looks like a job for an ambitious mature Type II civilization or an early Type III galactic society.


* Acceleration A (m/sec2) of a perfect photon rocket of mass M (kg) and power output P (watts) is given by: A = 2P/Mc, where c is the speed of light (3 × 108 m/sec).

17.4 Exotic Propulsion Systems
17.40 Exotic Propulsion Systems

john masefield

The exotic interstellar propulsion systems discussed in this section are all at the "idea" stage in human technological development. There is no guarantee that any or all of them can be made to work. A few have some theoretical support, but many do not.

Nevertheless, xenologists deem them important because of the likelihood that some may have advanced to the "profit" stage of exploitation in at least a few extraterrestrial Type II or Type III technological civilizations.

17.4.1 Gravity Catapults

A starship approaches a binary star
system whose members are both
white dwarfs orbiting each other
at close range.

Swinging in very near to one star on
the proper trajectory, the starcraft
benefits from gravitational slingshot
or Newtonian "gravity whip" effect.

The vessel withdraws orbital energy
from the stellar pair.
The most speculative gravity machine
of all is the Smoke Ring Catapult,
which consists of a rotating torus
of dense matter (such as neutronium)
turning inside out like a smoke ring.

Relativity theory predicts a force
in the direction of the rotation,
so a starship fired through the center
of the massive hoop could be kicked
up to very high velocities — depending
upon the rotational energy of the torus.

It is possible to conceive of "machines" that are capable of pushing a body, using gravitational force, up to fairly impressive suboptic velocities. These devices violate no known basic laws of physics, but it's difficult to see how to do the required engineering.

Contact Binary Catapult

The most "conventional" of these, first discussed by Freeman Dyson, has been called the Contact Binary Catapult.1023 A starship approaches a binary star system whose members are both white dwarfs orbiting each other at close range. By swinging in very near to one star on the proper trajectory, the starcraft benefits from gravitational slingshot or Newtonian "gravity whip" effect. The vessel withdraws orbital energy from the stellar pair.

Dyson estimates that a system involving two 1 Msun white dwarfs could accelerate delicate and fragile objects to a velocity of 0.7%c — at about 10,000 gees. Since there are no engines or propellants, there are no physical stresses on the payload — gravity acts on all parts of a material body equally. (Tidal forces, on the order of D/80 gees where D is starship diameter in meters, should not prove troublesome.)

Dyson also considered the possibility of using a pair of orbiting neutron stars as a gravity catapult. Unfortunately, they cannot exist! A neutron star binary would radiate away all of its orbital energy as gravitational radiation in less than 2 seconds. The two objects would coalesce almost immediately with a spectacular "gravity flash" at a frequency of about 200 Hz.

Black Hole Catapult

A more exotic technique is the Black Hole Catapult. This scheme requires that and find a rotating black hole (stellar mass) somewhere in space, then travel around it in the direction of spin very near to the equator. Besides losing a lot of time because of General Relativistic time dilation effects, some of the BH’s rotational energy would be converted to linear kinetic energy of the star ship. There would be a substantial increase in velocity. Tidal forces during transit will be rather extreme — about 500 million gees per meter — but apparently there are tricks with dense masses in a space vehicle that can be used to cancel the tides.2014 A Neutron Star Catapult is also possible, with similar effects.1099

Smoke Ring Catapult

The most speculative gravity machine of all is the Smoke Ring Catapult, which consists of a rotating torus of dense matter (such as neutronium) turning inside out like a smoke ring.2739 Relativity theory predicts a force in the direction of the rotation, so a starship fired through the center of the massive hoop could be kicked up to very high velocities — depending upon the rotational energy of the torus.

17.4.2 Antigravity and Reactionless Field Drives

A negative mass at rest beside a positive
mass would begin to accelerate.

Why should this be so? The negative
mass (which repels all matter) would
pus on the positive mass, but the
positive mass (which attracts all matter)
would pull on the negative mass.

If the two objects "weigh" the same,
they will chase each other and will
neither separate nor collide.

Energy and momentum is conserved,
since they each sum to zero.

Over the years the theme of antigravity and inertialess propulsion systems have been widely discussed, mostly in the fictional or pseudoscientific literature.

  • From H.G. Well’s cavorite gravity screen in his First Men in the Moon,
  • To such questionable propositions as the Biefield-Brown effect,137
  • Blackett’s Spin-Magnetic Coupling Theory1194 (which apparently inspired the late science fictioneer James Blish to write Cities in Flight with its "spindizzy drive"2809),
  • F. B. Hli’s Theory of Electrogravitics (see the lively debate in Cashmore and Gordon,1197,1199 Hli,1196 Hli and Okress,1201 Johnson and Hli,1198 and Okress1202),
  • Leonard G. Cramp’s G Field Theory,755
  • And of course the infamous Dean Drive (see Adams,2859 Campbell,1361 Cuff,2773 Davis,1371 Jueneman,2807 Klotz et al,2772 Pournelle,2806 and Stine2771), the idea has enjoyed a colorful and vituperative history.
  • A number of U.S. patents have been issued on supposed antigravity machines.2773
  • Even Einstein himself spent the last thirty years of his life searching for a unified field theory that would relate gravity and electromagnetism, and the search continues apace today.2774
Negative matter

To construct a gravity screen would theoretically require the ability to achieve gravitational polarization of matter.16 This would imply the existence of two very different kinds of matter — positive mass, which is attracted towards the Earth, and negative mass, which is repelled. At one time it was believed that antimatter might turn out to have negative gravitational mass,2692 but most physicists would dispute this today.1314,2952

Yet the search for negative mass continues. So far as we know there is no experimental evidence for negative matter, although it does appear in several solutions to the field equations in General Relativity. Papers by A.K. Raychaudhuri1521 and R. Mignani and E. Recami1519 suggest that tachyons may experience a gravitational repulsion to ordinary mass and thus may be interpretable as "negative matter," although because of their imaginary masses they will still fall towards a positive mass.

Besides gravity shields, negative masses, if they exist, could be employed directly for propulsion. A negative mass at rest beside a positive mass would begin to accelerate. Why should this be so? The negative mass (which repels all matter) would push on the positive mass, but the positive mass (which attracts all matter) would pull on the negative mass1190 If the two objects "weigh" the same, they will chase each other and will neither separate nor collide. Energy and momentum is conserved, since they each sum to zero.

A related concept is the idea of inertia control.
■ Gravitational mass
   represents the force of gravity
■ Inertial mass
   represents the force of physical acceleration.

The Eotvos experiment demonstrated that
the two kinds of mass are identical out to
eleven decimal places.

Presumably the negative mass could be created out of empty space if a positive mass of equal "weight" was created simultaneously. The net energy cost would be zero, since (-m)c2 + (+m)c2 = 0. To achieve reasonable starship accelerations, compact masses with densities like black holes should be used. Dr. Robert Forward elaborates:

What we really want to do is make a dense negative mass and a dense positive mass down in the engine room. We’d just pull them out of empty space, put a charge on the positive one and couple it with the spacecraft with electric fields. Now we have the two masses down in the engine room; they’re probably about 10-23 cm across and they weigh a little more than the spacecraft. The positive one is coupled to the spacecraft and the negative one pushes the positive one which pushes the spacecraft. Our vehicle’s acceleration can be as high as we can tolerate.2014

Inertial mass

A related concept is the idea of inertia control. Gravitational mass represents the force of gravity, and inertial mass represents the force of physical acceleration. The Eotvos experiment demonstrated that the two kinds of mass are identical out to eleven decimal places, under normal terrestrial conditions. But suppose we (or clever aliens) could arrange abnormal conditions which would allow the inertial mass of a chunk of matter to vary. When inertia is decreased, the same force imparts a higher acceleration; as inertial mass is brought close to zero, tiny forces would be able to produce huge accelerations. Lowering the inertial mass of fusion rocket propellant tanks would eliminate most of the normal constraints on lengthy interstellar missions for such vehicles.

Figure 17.5 Three Possible Antigravity Machines2014

Special Relativistic Antigravity Machine

Newton’s law of gravity does not obey Special Relativity. However, a "linearized" version of Einstein’s gravity theory (General Relativity) does. In this version, a mass flow gives rise to a "protational field" much as a charge flow gives rise to a "magnetic field" in conventional physics. This is called the "Lense-Thirring Effect."

The Special Relativistic Antigravity Machine is a torus wrapped in helical tubing. A dense mass flow is rapidly circulated through this tubing, causing a protational field to arise along the circumferential axis of the torus.

Just as a changing magnetic field generates an electric field, a changing protational field should generate a unidirectional gravity field. This field, directed upwards, would cancel planetary gravity and provide vertical propulsion.

General Relativistic Antigravity Machine

According to Einstein’s General Relativity theory, the presence of mass in a flat spacetime will cause that space to become curved. Mass is intimately connected with space — a rotating mass causes spacetime to "rotate" too.

The General Relativistic Antigravity Machine consists of a torus of dense mass which is turning inside-out like a smoke ring. A mass with this motion, according to Einstein’s theory, "drags the metric" through the center of the torus. Unidirectional general relativistic forces arise which are equivalent to gravity, and may be used to neutralize planetary surface gravity or as a space propulsion system.

Inertia Redistribution Antigravity Machine

While not widely accepted by theoretical physicists, there is a theory that the inertia possessed by all matter is a "tensor" quantity — that is, a multidimensional vector. In other words, inertia is not just a simple quantity but rather must be measured in the three separate directions of normal space.

The Inertia Redistribution Antigravity Machine does not destroy inertia or convert it into energy, but merely redistributes it in different directions. The starship to which the device is attached becomes "heavier" in the horizontal plane (thus imparting navigational stability) and "lighter" in the vertical direction. An object with minuscule inertial mass in one direction can be accelerated to fantastic velocities with negligible force.

Three other antigravity machines have been discussed by Robert Forward which involve no violations of the basic and established laws of physics (Figure 17.5).

Special Relativistic Antigravity Machine

The first of these, which he calls the Special Relativistic Antigravity Machine, involves a mathematical analogy between gravitational and electric fields.2740 A "linearization" of General Relativity gives a version of Newtonian mechanics which obeys Special Relativity. (Classical Newtonian mechanics does not.) In electromagnetism, something called charge is surrounded by a spherically symmetric electric field. In gravitation, something called mass is surrounded by a spherically symmetric gravity field. It may be said that the simple Newtonian gravity field is the gravitational analogue to the electric field.

Lense-Thirring Effect

The linearized General Relativity theory provides a similar analogy to magnetic fields. Much as a magnetic field is due to the motion of an electric charge or current flow, the linearized theory suggests that a moving mass, or "mass current," will give rise to a new kind of gravity field by a mechanism known as the "Lense-Thirring Effect."2890 Scientists plan to try to measure this field as it is produced by the rotating Earth in future satellite experiments.3320

Forward calls this new field a "protational field." He claims that, based on the existence of the field, an antigravity machine might theoretically be constructed in the shape of

…a torus with a tube wrapped around it, filled with very dense matter. If we started accelerating that mass flow through the tube around the torus, we would get a constantly increasing protational field, inside the torus. A changing protational field will create a gravity field just as a changing magnetic field will create an electric field. If we did it right, we would have an upward gravity field that could be used to cancel the field of the Earth.2014

General Relativistic Antigravity Machine

A second kind of antigravity machine suggested by Dr. Forward couples directly to "the fabric of space-time." His General Relativistic Antigravity Machine makes use of the notion that the presence of mass in a flat space-time causes a curvature, and that a rotating mass causes space-time to rotate too:

Imagine a rotating torus of dense mass, turning inside out like a smoke ring. An inside-out turning ring of very dense mass will create a force in the direction of the motion — a "dragging of the metric" as it is sometimes called. There will be general relativistic forces in the direction of the velocity of the mass. These forces are equivalent to a gravity field which again, theoretically, can be used to cancel the gravity field of the Earth.2014

And, as Willy Ley once pointed out, such a weightless body "would be squeezed out of the atmosphere by the weight of the air around it."2808

Inertia Redistribution Antigravity Machine

Finally, there is the Inertia Redistribution Antigravity Machine. The main principle behind inertia redistribution is the idea that inertia is a "tensor" quantity.2740 A tensor is just a multidimensional vector, so all this means is that we are accepting for the sake of argument the hypothesis that inertia may be a quality of matter that can be resolved into distinct directional components. That is, in our normal three-dimensional world, inertial mass becomes a three-dimensional quantity. While current experimental evidence does not support the tensor theory of inertia, if it is correct it leads to an interesting possibility for propulsion.

The main principle behind inertia redistribution
is the idea that inertia is a "tensor" quantity.

A tensor is just a multidimensional vector,
so all this means is that we are accepting for
the sake of argument the hypothesis that inertia
may be a quality of matter that can be resolved
into distinct directional components.

That is, in our normal three-dimensional world,
inertial mass becomes a three-dimensional quantity.

The Redistribution Machine does not get rid of inertial mass, but rather redistributes it so that some of it is pointing in new directions. If the machine makes the starship’s mass heavier in the horizontal plane and proportionately "lighter" in the vertical direction, a relatively tiny amount of force applied vertically would cause relatively large accelerations in that direction. The benefits are similar to those achieved using inertia control, discussed above, with the added advantage that inertia is conserved. (Note that since gravitational mass is unchanged, spacecraft will still feel the same attraction to planets and other massive bodies.)

Inertialess starships would have a number of interesting performance characteristics. Such a system must necessarily act upon every atom of the vessel in order to be effective. Far from any planet (so gravitational mass can be ignored), the inertialess craft could start and stop almost instantaneously. Since passengers have almost no inertia in the direction of flight, hideous accelerations can be tolerated (in that direction) with equanimity. For instance, if vertical/forward inertia is cut to 1% of normal and the ship accelerates at 100 gees, passengers would feel only an effective 1 gee of force. Inertialess starcraft would be virtually crashproof, since with no forward inertia people would not be thrown from their seats if an obstacle was struck. And, depending on how fast inertia can be suddenly redistributed, right-angle turns and hairpin bends should also be quite possible.

17.4.3 Tachyon Starships

Tardyons — normal matter

  • move at speeds less than the speed of light

Luxons — photons and neutrinos

  • particles which travel only at 100%c

Tachyons — unknown/undiscovered

  • particles restricted to superluminal velocities 

We have already mentioned the possibility of using tachyons for faster than-light communication. But could aliens use them for FTL space travel too?

Gerald Feinberg of Columbia University has divided all matter into three general classes:

  • Tardyons — particles which can move at any velocity less than the speed of light (normal matter)
  • Luxons — which can travel only at 100%c (photons and neutrinos)
  • Tachyons — particles restricted to superluminal velocities1492

All three classes may exist on the basis of Relativity theory.

The real technological trick will be to
discover a procedure for interconversion
which leaves undisturbed the essential
molecular relationships upon which life
and physical structure are based.
Coherent interconversion

If we desire to travel at hyperoptic velocities and achieve "true" FTL, somehow our starship must be converted from tardyon matter into tachyon matter at the start of the journey and then back again at the destination. While "conversion" may sound a bit like magic, actually it violates no laws of physics to presume it can be done. In fact, such conversion between classes of matter, to a limited extent, has already been verified experimentally.

Of course, no tachyons have been discovered yet. But nuclear physicists long have known that an electron and a positron, both tardyons, undergo "annihilation" when brought together with the release of two or three gamma-ray photons, which are luxons. Another example is the decay of the neutron, a tardyon, into among other things an antineutrino, which is a luxon. Still another example is "pair production," in which a gamma-ray (luxon) striking an atomic nucleus gives rise to an electron/positron pair (both tardyons). Conversion between tardyons and luxons, and back again, may be regarded as a verified physical phenomenon. There would seem to be no theoretical objection to conversion from tardyons to tachyons and vice versa, although the process may have to be moderated by luxon intermediaries.

The real technological trick will be to discover a procedure for interconversion which leaves undisturbed the essential molecular relationships upon which life and physical structure are based. Dr. Gregory Benford, nuclear physicist and science fiction writer, has suggested one highly speculative possibility in his story "Seascape":

In the laser the problem was simply to produce a coherent state — to make all the excited atoms emit a photon at the same time. Okawa reasoned that the same problem appeared in the faster-than-light drive. If all the particles in the ship did not flip into their tachyon states at the same time, they would all have vastly different velocities and the ship in one grinding instant would tear itself apart. Okawa’s achievement lay in finding a technique for placing all the ship’s atoms in excited tachyon states so that they could all be triggered at the same instant; the particles of the ship Jumped together, coherently. … All this was accomplished by maximizing the cross section for transition from real particle to tachyon. Complex modulated electromagnetic waves controlled the transition through microelectronic components, which operated on the scale of atomic dimensions.

Quantum mechanics predicts that it is
possible for particles to pass through
energy barriers which would otherwise
be "too high" for them to surmount.

Presumably, if we can get up close enough
to the lightspeed barrier, it may be possible
to "tunnel" across into tachyonland.

The starship will then have to lose energy
to go faster.
Quantum mechanical tunneling

Another conversion technique involves the use of the concept of quantum mechanical "tunneling." Quantum mechanics predicts that it is possible for particles to pass through energy barriers which would otherwise be "too high" for them to surmount. (This, in fact, is Hawking’s explanation for the evaporation of black holes.) Using the tunnel effect, a particle with insufficient energy to pass "over" a barrier instead passes "through" it. This peculiar behavior has been verified in the laboratory, and is exploited in modern electronic devices (e.g., tunnel diodes) as components in computer circuits.

Presumably, if we can get up close enough to the lightspeed barrier, it may be possible to "tunnel" across into tachyonland. The starship will then have to lose energy to go faster.

Complex "something" in "mass space"

A third technique for achieving superluminal tachyonic starflight has been suggested by Dr. Forward. Mathematicians have long known that certain wave phenomena can be represented by "complex numbers." A complex number is a two-dimensional quantity, having a real dimension and an "imaginary" dimension. (Recall our earlier discussion of the imaginary mass of tachyons.) Electronics engineers regularly use complex numbers to describe the behavior of alternating current (AC) circuits.

If physical mass can be represented mathematically as a complex "something" in "mass space," then objects in that space may be able to rotate to new orientations along the real and imaginary coordinate axes. Since tachyons have imaginary mass, a full 90o rotation would correspond to a conversion to tachyons. Says Forward:

Since we want the mass to be imaginary, we would have to get our spaceship off the real-line in that complex space and onto the imaginary-line. This would require that we make a right angle turn in mass space. When we do that, our ship becomes a tachyon.2014

Sights along the hyperoptic journey

Finally, what would tachyonic astronauts see during their hyperoptic journey? The tardyon and tachyon universes seem to possess symmetric equivalence, an intuitive observation borne out by careful mathematical reasoning.2770 Consequently, travelers in tachyonland should observe what appears to be another tardyonic universe (assuming there is as much tachyonic mass as tardyonic mass in all the cosmos). That is, a tardyon starship moving at 50%c in our universe which suddenly converts into tachyons will be traveling at an effective 200%c relative to our universe; but in the tachyon regime, where the vessel really is, it will still appear to be moving only at 50%c.

17.4.4 Momentum Interconversion Drives

Terran scientists know:

  • Electricity and magnetism are interchangeable
  • Mass and energy are interchangeable
  • Space and time are interchangeable
  • Angular and linear momentum may be similarly related  

Λ = (hG/2πc3)1/2 = 1.6 × 10-35 meters

  • The interconversion of only 45 billion atoms
  • — about 0.1 picograms of hydrogen —
  • Sufficient to propel a 100-ton starship at l%c

Terran scientists already know that electricity and magnetism are interchangeable, based on the work of James Clerk Maxwell in the 19th century. Mass and energy are too, according to Albert Einstein, as well as space and time. It is not unreasonable to hypothesize that angular and linear momentum may be similarly related.

Elusive physical constant

If such interconversion were possible, theory has it that some fundamental physical constant would be required, having the dimensions of length, to balance the mathematical equation involved. According to John Wheeler,2741 one of the fundamental constants of nature is the Planck length, written Λ, based on the Planck constant (h), the universal gravitation constant (G), and the speed of light (c).*

Robert Forward suggests that if we use the Planck length a suitable interconversion formula may be derived: Angular momentum (L) equals linear momentum (p) times the Planck length, or L = pΛ. Using this purely hypothetical relationship, it is simple to calculate that the destruction of a unit spin from a single tiny atom (about 10-34 kg-m2/sec) would yield 6.6 kg-m/sec of linear momentum. This means 6.6 kilograms of mass moving at 1 meter/second. The interconversion of only 45 billion atoms — about 0.1 picograms of hydrogen — would thus be sufficient to propel a 100-ton starship at l%c.

Stress-energy-momentum-mass tensor

The above scheme, of course, requires the violation of conservation of linear and angular momentum. This difficulty may be made somewhat more palatable in the following way. Physicists recognize that the source of gravity in General Relativity theory is what is called the "stress-energy-momentum-mass tensor." That is, mass alone isn’t the only source of gravity. Kinetic energy, stress energy, linear and angular momentum also contribute to the field.

We already know that mass and energy can be interconverted, according to the relation E = mc2. It may turn out to be possible to interconvert everything in the stress-energy tensor, perhaps according to an equation like E = mc2 = pc = Lc/Λ. Vast amounts of propulsive energy would become available. Says Forward:

If we took one unit of spin which is 10-34 units of angular momentum (very small), we would get 6.6 kg-m/sec of linear momentum or 10-8 kg of mass or, equivalently, 109 joules of energy — all from one atom.2014


* The formula Wheeler gives is: Λ = (hG/2πc3)1/2 = 1.6 × 10-35 meters.

17.4.5 Statistical Transport

In the Uncertainty Theory, a particle
cannot be said to have a fixed position
in space but has a very small, though finite,
probability of being anywhere in the universe.

All you had to do, therefore, to get an
instantaneous mode of transport was
to manipulate the Heisenberg equations
until you were more likely to be somewhere
else than where you started, and — presto!

Starships using the Heisenberg Drive "move"
by going from maximum probability
of existence at one position in the universe,
through universality, to maximum probability
of existence at another position elsewhere.

The mysterious, often apparently "magical" results of modern quantum physics have enticed many writers to try their hand at devising propulsion systems based on the principles of quantum mechanics and statistical thermodynamics. Most of these fall reliably into two general categories: Bootstrap Drives and Heisenberg Drives.

Bootstrap Drive

To visualize a Bootstrap Drive, consider a cylindrical vessel filled with ordinary gas. Although each of the molecules is rushing madly about at speeds in the kilometer/second range, the net effect of trillions of particles darting in random directions is a wash-out. The molecule motions are averaged out over the walls of the container, yielding a net system velocity of zero.

About half a century ago, the late John W. Campbell, Jr. suggested that it might be possible to devise an external field that would induce the molecules subject to its influence to assume the highly improbable state of collective upward motion.1110 Much of scientific experimentation involves the judicious rearrangement of probabilities to achieve desired results, so this idea is certainly not impossible. The result would be a reactionless Bootstrap Drive that could be used to propel spaceships to other worlds.

Miniscule probabilities

It is fairly clear that the technology to achieve a bootstrap effect will not be trivial. The magnitude of the difficulty may be made plain with a fairly simple example. Imagine a pan containing a liter of water, placed on a stove that can bring it to a full boil in 15 minutes. Our experiment consists simply of heating the liter of water to the boiling point over and over again. According to the laws of statistical thermodynamics, there is a very small but nonzero probability that during one experimental cycle the molecules will spontaneously arrange themselves in crystalline form — that is, freeze instead of boil. But calculations show that this event is so improbable that it is expected to occur only once in every 1010,000,000,000,000,000,000 years, assuming 15 minute cycles. Clearly, to enhance such miniscule probabilities will not be easy.

But if it could be done, the Bootstrap Drive would permit a container of gases to move on its own without the ejection of any reaction mass. The ship would rise up, so to speak, by tugging on its own bootstraps. In normal operation, the Bootstrap Drive would give up thermal energy and become very cold. To maintain the propulsive force, it should be necessary to supply additional energy to the system in the form of heat.

Heisenberg Drive

In the 1940s Campbell also came up with a number of starship propulsion system designs operating on Heisenberg’s Uncertainty Principle in quantum mechanical theory. Arthur C. Clarke describes the functioning of the Heisenberg Drive:

In the Uncertainty Theory, a particle cannot be said to have a fixed position in space but has a very small, though finite, probability of being anywhere in the universe. All you had to do, therefore, to get an instantaneous mode of transport was to manipulate the Heisenberg equations until you were more likely to be somewhere else than where you started, and — presto!1110

In essence, starships using the Heisenberg Drive "move" by going from maximum probability of existence at one position in the universe, through universality, to maximum probability of existence at another position elsewhere.2642

17.4.6 Black Holes and Space Warps

Figure 17.6 Using Black Holes for Interstellar Travel

The Wormhole

In the Einstein-Rosen model of the nonrotating black hole, a wormhole connects portions of two separate flat-space-time universes. This wormhole, called the Einstein-Rosen Bridge, may be interpreted either as connecting two distinct universes or as joining two distant points in the universe of origin. According to this theory, starships passing through the event horizon of a black hole would find the curvature of space-time growing less severe, eventually emerging through a "white hole" in distant space.2954

The diagram on top shows the Einstein-Rosen Bridge as it might connect two distant points in the same universe. The event horizon lies at the center of the wormhole.

The diagram on the bottom is an "unfolded" version of the Bridge, for those who would rather view universal space-time as essentially flat.

The two are mathematically equivalent

Kruskal Diagram for Rotating Black Holes

The figure at right represents a possible space-time configuration of a rotating black hole, using "Kruskal coordinates." There are now two event horizons instead of one, so there are three classes of space./p>

  • It is possible to reach other universes like ours by selecting the correct trajectory upon entering the black hole. (Trip C)
  • A collision with the ring singularity is possible. (Trip B)
  • Cowardly astronauts can avoid the black hole altogether. (Trip A)
  • Some "Type I" universes cannot be reached at all until tachyonic star travel is permitted .(Trip D)
Folded Kruskal diagram

The Kruskal diagram of the Kerr solution to the equations describing rotating black holes may be folded cylindrically as shown in the diagram at right.

  • Using this interpretation of the wormhole caused by a rotating BH, a starship is theoretically capable of circumnavigating the entire Kruskal space-time and returning to the universe of origin anywhere in space and anywhen in time.
  • This would appear to violate causality and permit time travel.
Wormholes

Severe gravitational distortion of space-time offers several scientifically plausible mechanisms for extremely fast interstellar communication and travel.2798 Dr. John A. Wheeler of Princeton University has predicted the existence of "wormholes" — a warpage of free space — based on his own version of General Relativity which has come to be known as geometrodynanics.2741

Wheeler wormholes should be exceedingly small (subatomic dimensions, say, about 10-35 meters). They would allow point-to-point linkages of all locales in the universe; pointlike particles, such as electrons, could be used to communicate without traversing the intervening space. Wheeler draws an analogy to the sea:

Space is like an ocean which looks flat to the aviator who flies above it, but which is a tossing turmoil to the hapless butterfly which falls upon it. Regarded more and more closely, it shows more and more agitation, until … the entire structure is permeated everywhere with worm-holes Geometrodynamic law forces on all space this foam-like character.77

J.C. Graves and D.R. Brill at Princeton have shown that electric field lines threaded through the throat of a wormhole may prevent it from closing.2777 Such a tunnel in space should stay open indefinitely, allowing particles of matter to pass through to known destinations. Wormholes may connect a vast number of alternative universes at the subatomic level.2778

Rotating black holes

Black holes, predicted in 1939 by Oppenheimer using General Relativity theory, are concentrations of mass so dense that even light cannot escape the tremendous gravitational pull. Stellar-mass BHs are typically several kilometers in diameter. The standard black hole model predicts a "singularity" at dead center, a point at which density becomes infinite, This collapse of physical laws as we know them, fortunately, is hidden from view behind an event horizon — the surface below which photons cannot escape.

However, in the case of a rotating black hole things are quite different. According to relativistic solutions first obtained by R.P. Kerr in 1963, the singularity is no longer a point but has expanded into a ring.2742 Many theorists believe that the region lying in the disk of the ring singularity may be a gateway to other universes or to our own universe at a different point in space and time. Rotating BHs have two event horizons instead of one, passage through which by a starship may involve such peculiar phenomena as negative mass effects and time running in reverse.2746 The Kruskal Diagram illustrated in Figure 17.6 shows one interpretation of possible trajectories through a rotating black hole assuming a Kerr spacetime metric.2747

A few writers have offered fabulous accounts of galactic commerce among sentient extraterrestrial races, using black holes as the entry gates to a kind of hyperspatial subway system.* Says astronomer Carl Sagan:

I can imagine, although it is the sheerest speculation, a federation of societies in the galaxy that have established a black hole rapid-transit system. A vehicle is rapidly routed through an interlaced network of black holes to the black hole nearest its destination. … Great civilizations might grow up near the black holes, with the planets farthest from them being designated as farm worlds, ecological preserves, vacations and resorts, specialty manufacturers, outposts for poets and musicians, and retreats for those who do not cherish big city life. In such a galaxy the individuality of the constituent cultures is preserved but a common galactic heritage established and maintained. Long travel times make trivial contact difficult, but the black hole network makes important contact possible.15

Folded Kruskal diagram

There are a number of practical difficulties associated with the use of BHs as an interstellar rapid-transit system. First, there is the problem of navigation. Until you jump into a black hole, you don’t really know where you will end up. Once you emerge at your destination (from a "white hole"), it is difficult to know how to get back. Many theories predict that it may be impossible to return. If you have entered another universe, the journey is probably irreversible and strictly one-way; if you have remained in your own universe, it would be an extraordinary stroke of luck to find another rotating BH in the immediate vicinity whose exit terminus happens to lie near the original starting point.

Tidal forces are yet another problem. Astronauts venturing even within a few hundred kilometers of a stellar-mass black hole would be savagely ripped apart by the simultaneous squeezing and stretching forces which would amount to hundreds of gees. While it may be possible to compensate for these effects by using special arrangements of ultradense matter within the starship structure, it may be better instead to search for supermassive black holes. Several theoretical physicists have proposed that gigantic BHs may exist at the center of many galaxies — possibly even our own — with masses ranging from 106-1010 solar masses. Surprisingly, such monstrous objects need be no more dense than air, and tidal forces would be measured in milligees rather than megagees at the event horizon.

Catastrophe theory, first devised by French mathematician Rene Thom more than a decade ago,2800 offers a totally new conceptual variation on the theme of space warp drives. Catastrophe theory is a controversial new mathematical tool for examining highly discontinuous events — such as bridges buckling, sudden economic depressions, rapid emotional changes from fear to rage, and a host of other abrupt alterations in physical structures, lifeforms, and societies. The theory explains how slight changes in the initial state of a system can result in major divergence in the course of its evolution and subsequent behavior.

Since the Big Bang was a highly discontinuous event, creating a universe out of nothingness, it is quite conceivable that a catastrophe cosmology may eventually be devised. Perhaps it would involve catastrophe surfaces rather than simple spherical space-time geometry. Indeed, the coordinates need not all be spatial or temporal, but could include axes representing energy, momentum, spin, mass, charge, angular velocity, or whatever else is appropriate. If this is so, then the proper combination of fields and physical parameters could cause a packet of photons (a message) or a chunk of matter (a starship) suddenly to assume new parameters in a single, "catastrophic" leap. These new parameters might correspond to changes in energy, spatial position, or time.


* We will not here discuss the fascinating possibility of tachyonic black holes, although these have already been investigated theoretically.1520

17.4.7 Teleportation and Transporter Beams

Booth technology would also make possible a device
which Arthur C. Clarke has called the Replicator.

The Replicator has access to a vast library
of information which specifies all known physical
objects and consumer goods, and is able to
reproduce any number of exact copies of them at will.

If practical matter transmutation is also available,
bags of sand could be dumped in at one end and
Univacs and Mona Lisas would emerge from the other.
Teleportation Booth

The first type of matter transfer system we’ll consider may be called the Teleportation Booth. To travel, the subject is seated in the transmission chamber. Complete data on the composition, position, and energy states of each atom in his body are read out by means of a sophisticated scanning device, and recorded in computer memory. The original may or may not be destroyed. The data is transmitted at the speed of light (radio waves) or faster (using tachyons) to a distant receiver, which picks up the data and places it in the memory banks of a second computer. A new human body, an exact duplicate right down to the last atom, is then reconstructed using the information taken from the original. The replica emerges from the booth, indistinguishable from the original in every way.*

If you think about this scheme, what has been accomplished here is not true matter transmission but rather transmission of information about matter. There is nothing fundamentally impossible about this process. In fact, in one dimension — sound — the problem may be regarded as solved by human technology. With the very finest audio equipment, duplicated sounds can no longer be distinguished from the original variations in air pressure that caused them. Further, these "replicas" can be transmitted over vast distances by radio waves.

Television represents the solution in two dimensions. In a typical system, a sophisticated TV vidicon scanner reads the information from the surface of, say, a human face, transmits the data to distant receivers, and the image is reproduced on the picture tube. Admittedly the visual reconstructions are far from perfect, but the electronics engineers are busily working to correct that defect.

Figure 17.7 Teleportation Booths: Precursor Technology on Earth

Biostereometrics

Biostereometrics is a new scientific discipline which allows the three-dimensional measurement of living things using techniques similar to aerial mapping. The figure at right is the result of a low-resolution computer-generated optical replica of a male human body. The data stored in the computer may be used to rotate the replica to any angle or position, or to "dissect" the figure and examine any single part in greater detail.2835

CAT Scanner

As for the present state-of-the-art in examining the insides of human bodies, the "CAT Scanner" is about the best there is. Essentially an automated x-ray machine, the Scanner looks at the body in very thin slices and can detect variations of only a few percent in transmitted intensity. The photos BELOW are a Scanner record of a human female across the chest area, showing the spine, aorta, and even a small pancreatic cyst just to the right of the spine and aorta.2835

X-ray Holography

At right are the first direct images of atoms of magnesium, oxygen and carbon in a section of crystal, using a technique called x-ray holography in conjunction with a digital computer system.2810

The Teleportation Booth is the answer to information transfer concerning three dimensions. It operates in such a manner as to transmit a 3-D image through space. As with radio and television, the original goes nowhere.

It is entirely possible to imagine the construction of the Booth by making a direct extrapolation of currently-foreseeable human technology (Figure 17.7). Our present techniques of x-ray diffraction scanning, neutron-beam crystallography and field-ion microscopy easily permit resolutions at the atomic level (say, 1 Angstrom),419,2801 and subatomic scanning is already available using large cyclotrons and linear particle accelerators. Indeed, high energy neutrino beams have been used to examine details of subnuclear structure as small as 10-18 meter, or about 0.00000001 Angstroms.2825

How about computer memory? Ten terabit (1013 bits) memories are already available for use in Booth construction.583 Will this be enough? The human body consists of roughly 3 × 1027 atoms, so at first blush we might expect that at least 1028 bits of information should be needed to completely specify the human transmittee. Fortunately, the vast majority of these data are redundant. Our genes, a considerably more compact specification or "blueprints" for our bodies, represent only about 1010 bits. Our brains, however, contain at least 1013 bits of information — so this turns out to be the limiting factor.

Electro-optical modulation

According to Tim Quilici of Collins Telecommunications Systems Division of Rockwell International, a fairly new technique called electro-optical modulation may soon permit transmission rates through space of 1010 bits per second per channel.2779 The information detailing the construction of the human body thus could be completely transmitted, perhaps using a 1 mm infrared space-based laser beam, in just one second — although it would require another twenty minutes for the subject’s entire brain-map to arrive, if only one data channel is utilized.

Once the information has been received, the subject could be physically reconstituted using an extended and more exact version of the present-day techniques of molecular beam epitaxy, electron beam microfabrication, or some similar process.2804 The living subject would probably have to be assembled cold, close to absolute zero dissociative and degenerative chemical reactions, and would later be warmed and reanimated. It would seem that the Teleportation Booth is a great way to scatter copies of one’s self throughout the universe or across a planet, but it is a lousy way to travel — because you don’t go anywhere.**

The Replicator

Booth technology would also make possible a device which Arthur C. Clarke has called the Replicator.55 The Replicator has access to a vast library of information which specifies all known physical objects and consumer goods, and is able to reproduce any number of exact copies of them at will. If practical matter transmutation is also available (see Chapter 19), bags of sand could be dumped in at one end and Univacs and Mona Lisas would emerge from the other.

The Transporter Beam
This system, familiar to viewers of the television series Star Trek
Involves what computer specialists refer to as "destructive readout"

■ The transmittee is somehow converted into patterned electromagnetic radiation
■ Which is fired across space
■ Reassembling itself back to normal matter at a predetermined "focus"
■ The original is destroyed during the conversion into photonic radiation
■ Only a transmitter is required
■ Subject self-assembles at destination without assistance of a receiver mechanism
Transporter Beam

The second major class of matter transmission techniques is called the Transporter Beam. This system, familiar to viewers of the television series Star Trek, involves what computer specialists refer to as "destructive readout." The transmittee is somehow converted into patterned electromagnetic radiation which is fired across space, reassembling itself back to normal matter at a predetermined "focus." The original is destroyed during the conversion into photonic radiation. Only a transmitter is required and the subject is self-assembling at the destination without the assistance of a receiver mechanism.

Such a procedure, while seemingly improbable, is not wholly inconceivable in terms of modern science. We know that electrons can be converted into patterns of gamma rays by the addition of positrons. Furthermore, optics theory tells us that unsynchronized light waves give rise to regions of destructive and constructive interference. If the phase and frequency of electromagnetic radiation could be forced to enter into constructive interference in a compact volume of space, pair production might be initiated along with other related processes giving rise to structured matter. Or, if the theory held by a few physicists that mass consists of "standing light waves" has any plausibility, then it might be possible to induce the spontaneous conversion of energy into matter at remote points. The real trick would be to retain the complex structure of the living organism throughout the process of beamdown, and to handle the nearly 1019 joules of interconversion energy without mishap.

Matter Transposition

A third major class of teleportation technology, known as Matter Transposition, involves the passage of physical objects from point A to point B without traversing the intervening space (and without being destroyed or merely duplicated). In this case it is the original who completes the journey, unharmed. Similar in concept to the idea of space warps discussed earlier, transposition depends on the proposition that space is not only curved, as predicted by General Relativity, but is also wrinkled and discontinuous.

To make a trip, some mechanical or electronic device is used to render two points in space — say, where the passenger is and where he wants to go — contiguous. The subject is then fixed in the new position, and space allowed to snap back to its original configuration. As Donald Wollheim describes the process:

Two segments of space may be separated by thousands of light-years traveling along the visible three-dimensional continuum of space, yet may be touching each other like two pages of a book. The Gate then is merely an extradimensional means of cutting across this touching point and thereby avoiding the problem of having to travel those thousands of light-years inch by inch.984

If it turns out to be theoretically possible to selectively bend space-time locally by artificial means, the technological problems will be immense. For one thing, the energy required to adequately bend space would probably be prohibitive over distances of more than a few kilometers. A stellar-sized black hole, the best space-warper known to human science, has a mass-energy on the order of 1048 joules. This represents the entire power output of a mature Type III civilization for ten seconds, and yet the BH causes severe distortion of space-time over distances of less than 100 kilometers. Also, as Larry Niven has pointed out, the simultaneous operation of two or more Matter Transpositors in close proximity could prove embarrassing.2744 At best, space would be bent in some unanticipated way, causing transmittees to arrive at some arbitrary and unscheduled destination. At worst, passengers could wind up gravitationally collapsed.

Tunnel Transporter

Two other teleportation schemes also involve the idea of point-to-point transmission without crossing the intervening space. The first of these, and easiest to understand, is the Tunnel Transporter. This hypothetical device operates on the same principle of quantum mechanical tunneling discussed earlier in connection with tachyon starships. Explains Larry Niven:

Apparently physics students are now taught that a tunnel diode takes an electron here and puts it there without allowing it to occupy the intervening space. If you can do it with quantum physics, why not with larger masses? With people? The theory looks good, and it hasn’t been used much in science fiction.2744

Fourier Transporter

The second teleportation scheme, called the Fourier Transporter, requires a bit more explanation.2780 In the early 19th century, a brilliant French mathematician and physicist by the name of Baron Jean Baptiste Fourier determined that almost any function of a real variable could be mathematically represented as a sum of sine waves, each of whose wavelengths are integral multiples of the variable. Any three-dimensional function can be transformed mathematically into "Fourier space," a coordinate system which uses inverse wavelength for the axes rather than spatial position.

An object sitting in space near Sol has a representation in Fourier space (say, S) that is distinctly different from the representation of that same object in orbit around the star Arcturus (say, X). Terrestrial electronics engineers already know how to build digital "filters" that will accept any input S and output any response X in one dimension. The Fourier Transporter works as follows.

A device near Sol transforms a passenger, by means unspecified, into Fourier space as S. A universal filter, driven by a computer which calculates what X must be in accordance with the traveler’s itinerary, almost instantly converts S into X. The device then performs a reverse Fourier transform on X-and the passenger is gone! He emerges from Fourier space to find himself in orbit around Arcturus.

The validity of Fourier transforms out to mathematical infinity is crucial to the successful operation of the Transporter. If, as some have suggested, Relativity only limits the velocity of transfer of mass-energy and not information, then it might be possible to transmit information very quickly without using any form of mass-energy to do it.2014 The Fourier Transporter would thus provide virtually instantaneous travel, at little or no cost in energy.


* Some of the natural philosophy and pragmatic aspects of matter transmission may be found in Cleaver,1167 Elliott,1162 Gooden,1165 Lawden,1170,1164 and Niven.2802 [Ed. Note: And the Saga of the Cuckoo.]

Error rate

** There is an interesting side issue respecting the accuracy of transmission. It is well-known among radiation scientists that the random alteration of one out of every 108 atoms in the human body will produce death. That is, if more than one atom in every 100,000,000 transmitted by the Booth is erroneous, the passenger will get sick and probably die of symptoms resembling acute radiation poisoning.380 A Teleportation Booth with an error rate of 109 bits/error would allow people to make only ten successive trips through the machine before death ensued.

17.5 Time Travel
arthur buller


One-way time travel into
the future is no problem at all.

Each of us is doing it right now,
at the constant rate of 24 hours/day.

The problem is how to alter that rate.
D = V × T

Interstellar journeying ultimately depends upon manipulating the formula D = V × T.

Where D is distance, V is velocity, and T is time. So far we have discussed only the possibilities of increasing V or of decreasing (or abolishing altogether) D. But there is a third option available. Alien or human technologists may somehow manage to reduce or otherwise circumvent T.*

One-way time travel into the future is no problem at all. Each of us is doing it right now, at the constant rate of 24 hours/day. The problem is how to alter that rate.

Time dilation of motion

We’ve already taken a quick look at relativistic time dilation. Time passes more slowly far moving astronauts than for those who are standing still. For example, a person traveling at a constant 99%c through space may also be said to be traveling through time at the reduced rate of 3.4 hours/day (hours personal time/standard Earth observer day). In case anyone is interested, the time dilation rate may be calculated according to the following relation: T = t(1 - v2/c2)1/2, where T is shipboard time and t is stationary observer time. And time dilation is not just some theoretician’s pipe dream, either. In 1971 two American physicists, Joseph Hafele and Richard Keating, decided to test Relativity and see if they could make themselves age a tiny bit more slowly. They purchased tickets on a jumbo jet for an around-the-world flight, taking with them an atomic clock, accurate to one billionth of a second, to measure more precisely the passage of time. The aircraft flew at 600 mph, or about 0.00009%c, circumnavigating the planet. When the trip was over the moving clock — and the two scientists themselves — had lost more than 10-8 seconds. That is, for most of the flight, personal time had been passing at the decreased rate of 23.999 999 999 9996 hours/day.2891

A playwright could enter the fast-time chamber at
3 PM one afternoon, spend two weeks writing a play,
and emerge at 4 PM the same day in time for tea.


This could have a number of interesting technical
and social consequences.

Time dilation of massive objects

The time dilation caused by motion is a product of Special Relativity. But similar effects occur near massive objects. According to General Relativity, time moves more slowly close to matter than far from it. In other words, mass makes time slow down. For instance, on the surface of Earth we age about 24 hours/day. But in free space, far from any planet, time speeds up and we age slightly faster — about 24.000 000 016 hours/day.**

Near a stellar-sized black hole we could expect time delays ranging from miniscule to enormous (but watch out for the tides). Judicious selection of proper hyperbolic orbits could get our aging rate down to microseconds/day or less.2636 The tides can be avoided by seeking out a supermassive galactic BH — perhaps 108 Msun or so — to perform the experiment. Or, if we could collect or manufacture lots of extremely dense matter, we will discover that time also runs slower inside a heavy mass,2014 We might construct a hollow spherical shell of dense matter either on Earth or in orbit, and we’d have a one-way time machine. There is no gravity inside a hollow sphere due to mass in the shell, and no tides either. But time would pass more slowly inside the passenger chamber. If he could see out, the world might appear to flash by much as in the movie classic The Time Machine; to outside observers looking in, the time traveler would seem to be moving in slow motion.

If it is deemed useful for some reason, it may also be possible to increase the rate at which time passes. A hollow sphere constructed of extremely dense negative mass would greatly speed up time throughout its interior. This could amount to years/day rates or more. A British playwright could enter the fast-time chamber at 3 PM one afternoon, spend two weeks writing a play, and emerge at 4 PM the same day in time for tea. This could have a number of interesting technical and social consequences.2020

The Grandfather Paradox goes something like this:
■ You build a time machine and use it to go back
    80 years in time.
■ Your grandfather, whom you dearly despise,
    is a babe-in-arms, so it's an easy matter to dispatch him.
■ But now he doesn’t live to marry your grandmother,
    so your father is never born and neither are you.

So you don’t exist.
■ Worse, the time machine that caused all the trouble
     doesn't exist either since you weren’t around to build it.
■ But then you couldn’t have gone back in time to kill your
    grandfather, so he lived, so you were born, so the time
    machine was built … etc. — a real paradox.
Travel into the past

What about travel into the past? Traditionally, this has been considered quite impossible because of violations of causality (the proper relationship between cause and effect) that could occur. Causality problems are commonly illustrated in terms of the Grandfather Paradox, which goes something like this: You build a time machine and use it to go back 80 years in time. Your grandfather, whom you dearly despise, is a babe-in-arms, so it is an easy matter to dispatch him. But now he doesn’t live to marry your grandmother, so your father is never born and neither are you. So you don’t exist; worse, the time machine that caused all the trouble doesn’t exist either since you weren’t around to build it. But then you couldn’t have gone back in time to kill your grandfather, so he lived, so you were born, so the time machine was built … etc. — a real paradox.

Multiply connected space-time

Such difficulties do not deter the stout of heart and firm of nerve. F.J. Tipler, a physicist associated with the University of Maryland, recently published a paper in Physical Review (a highly respected journal) in which he proposed that General Relativity can be used to design a two-way time machine.2894 Tipler suggests the construction of a dense cylinder of mass, spinning with a tangential velocity of at least 50%c at the circumference. This, he claims, should give rise to a very unusual region of space-time — called "multiply connected space-time" — existing outside the physical boundary of the mass itself.

According to Tipler, any past or present event in the known universe could be reached by passing through the "multiply connected" region near the middle, but outside, of the spinning cylinder. Starting at any point (x, y, z, t) and traveling at suboptic velocities around the special region in the proper way, a starship can return to point (x, y, z) at any time t ± Dt — past, present, or future. Tipler makes his prediction explicit: "In short, general relativity suggests that if we construct a sufficiently large rotating cylinder, we create a time machine."

It remains to be seen whether Tipler’s proposal can withstand critical review, but it remains a tantalizing possibility nevertheless.


Literature on time travel and the nature of time

* The literature on time travel and the nature of time is enormous.

  • For fictional treatments of time travel:
    Interested readers are referred to Anderson,2795 Asimov,2817 Gerrold,2819 Hoyle,2818 Snatsky,636 Vonnegut,2480 and Wells2796
  • For conceptual and theoretical treatments of time and time travel:
    Refer to Edwards,1166 Finkelstein,1502 Fraassen,905 Gardner,644 Lucas,1859 Meerloo,903 Niven,2743 Taylor,1190 and Whittrow1847

** For the mathematically-inclined reader, the formula for the general relativistic time dilation rate (t) as a planetary mass (M) is approached to a distance R is given by: t = T(1 - 2GM/Rc2)1/2, where T is free-space time, G is the universal gravitation constant, and c is the speed of light.

17.6 Interstellar Navigation

Table 17.5 Wavelength of 5000 Angstrom Laser Light

Communication Signals Received by a Relativistic Starship

table 17 5 wavelength of 5000 angstrom laser 400

Problems at higher speeds.


Two distorting effects
begin to dominate:


Aberration and Doppler Shift

Without some means of navigational control, any interstellar transport system is useless. As we shall see presently, relativistic starship navigation is hardly a trivial affair.

At only 1-10%c there are few problems. Just set the crosshairs on the target star, the home star, and three reference stars to either side, and the ship’s navigator can calculate velocity and heading fairly exactly. Problems begin to crop up at higher speeds, however. Two distorting effects begin to dominate: Aberration and Doppler Shift.2745,1160

 Aberration of starlight 

Click for Synopsis   

Aberration

  • Causes stars to appear to be displaced forward into the direction of flight

Analogous to raindrops streaking side-windows of a speeding train

  • Rain is falling straight down
  • But streaks on window run diagonally, slanting downward from the front
  • As if the source was ahead rather than above

Aberration of starlight

  • Similarly, causes stars to appear farther forward than they really are
  • At relativistic velocities the effect can be extreme

As the speed of light is approached

  • Stars will appear to move to the front and huddle together
  • In a small patch directly in the line of flight
  • The rest of the sky is black
Aberration

Aberration causes stars to appear to be displaced forward into the direction of flight. The situation is analogous to raindrops streaking the windows of a speeding train. Although we know the rain is falling straight down, the streaks on the window run diagonally, slanting downward from the front as if the source was ahead rather than above. Aberration of starlight, similarly, causes stars to appear farther forward than they really are. At relativistic velocities the effect can be extreme. As the speed of light is approached, stars will appear to move to the front and huddle together in a small patch directly in the line of flight. The rest of the sky is black.

 Doppler Shift of starlight 

Click for Synopsis   

Doppler Shift

  • Applies to light as well as sound
  • The changing pitch of a moving siren as it passes the listener is an example of this effect

On board a starship, Doppler Shift will:

  • Blue-shift light from approaching stars (looking forward)
  • Red-shift light from receding stars (looking astern)

Therefore:

  • Suns ahead of the vessel in the line of flight will become bluer in color
  • Those behind will become redder

At 37%c:

  • A starship leaving Sol would no longer be able to see it
  • Sol’s light, severely red-shifted, would have moved into the infrared and be invisible to human eyes
  • If destination is Alpha Centauri, it also is invisible having been blue-shifted up into ultraviolet range

As velocity increases still more:

  • A growing zone of darkness appears directly sternward
  • It grows larger as the ship picks up speed
  • A similar patch of starless blackness develops toward the bow

At 50%c:

  • The cone of invisibility distends an angle of 30° forward and more than 60° astern
  • The only stars that are still visible are crammed into a "barrel" surrounding the starcraft
  • The forward rim of the Star Barrel is seemingly dominated by brilliant blue-white stars

Sweeping the eye upwards and rearward:

  • The hue of star light changes from blue to green to yellow to orange to red, then to blackness
  • All the familiar constellations are compressed and distorted beyond recognitionMounting speed forces the Barrel slightly backwards, then forward again
  • Compacting still narrower with even more vivid coloration
  • The Barrel has now become what Eugene Sänger once called the Starbow

At 99%c:

  • The Starbow is now an annular rainbow-hued ribbon of color leading the spacecraft
  • It is 12° wide with its forward edge raised up 23° from the line of flight
  • The rest of the sky it jet black
  • Precise navigation by external fixes has become utterly impossible
  • The starship pilot must rely on a system of dead reckoning or inertial guidance
Doppler Shift

Doppler Shift applies to light as well as sound. The changing pitch of a moving siren as it passes the listener is an example of this effect. On board a starship, Doppler Shift will blue-shift light from approaching stars (looking forward) and red-shift light from receding stars (looking astern). So suns ahead of the vessel in the line of flight will become bluer in color; those behind will become redder.

At 37%c, a starship leaving Sol would no longer be able to see it. Sol’s light, severely red-shifted, would have moved into the infrared and would be invisible to human eyes. If the destination is Alpha Centauri that star would also be invisible, having been blue-shifted up into the ultraviolet range.

As velocity increases still more, a growing zone of darkness appears directly sternward. It grows larger as the ship picks up speed. A similar patch of starless blackness develops toward the bow. At 50%c, the cone of invisibility distends an angle of 30° forward and more than 60° astern. The only stars that are still visible are crammed into a "barrel" surrounding the starcraft. The forward rim of the Star Barrel is seemingly dominated by brilliant blue-white stars. Sweeping the eye upwards and rearward, the hue of star light changes from blue to green to yellow to orange to red, then to blackness. All the familiar constellations are compressed and distorted beyond recognition.

Mounting speed forces the Barrel slightly backwards, then forward again, compacting still narrower with even more vivid coloration. The Barrel has now become what Eugene Sänger once called the Starbow.2783 At 99%c the Starbow, now an annular rainbow-hued ribbon of color leading the spacecraft, is 12° wide with its forward edge raised up 23° from the line of flight. The rest of the sky it jet black. Precise navigation by external fixes has become utterly impossible, and the starship pilot must rely on a system of dead reckoning or inertial guidance.

 Starship communication 

Click for Synopsis   

Communications between starship and home planet become problemmatical as the vessel
moves off at relativistic speeds

  • There will be a growing time delay due to rapidly increasing distance
  • Also the frequency of the signals received will be altered

If the communication system uses laser transmitters tuned to monochromatic green light
at exactly 5000 Angstroms changes in frequency at the receiver are as shown in Table 17.5

  • A receding starship sees the green light as infrared for speeds above 50%c
  • At excessive suboptic velocities as microwaves
  • Conversely, an approaching vessel sees ultraviolet signals above 50%c
  • X-rays above 99.9%c
Starship communications

Communications between starship and home planet become problemmatical as the vessel moves off at relativistic speeds. Not only will there be a growing time delay due to rapidly increasing distance,1091 but the frequency of the signals received will be altered. If the communication system uses laser transmitters tuned, say, to monochromatic green light at exactly 5000 Angstroms, then the changes in frequency at the receiver are as shown in Table 17.5. A receding starship sees the green light as infrared for speeds above 50%c, and at excessive suboptic velocities as microwaves. Conversely, an approaching vessel sees ultraviolet signals above 50%c and x-rays above 99.9%c.

Other interstellar navigation hazards

There are many other hazards to interstellar navigation which we can only briefly mention here.

  • Relativistic starcraft will be subject to radiation damage and erosion caused by the impact of interstellar dust and hydrogen atoms.2761
  • Besides irradiation of the crew, there will be extreme heating effects on the starship forebody at near optic speeds — without magnetic shielding, forebody surface temperature could reach 3010 K at 99.9%c in a 1 atom/cm3 interstellar medium.1116
  • Besides the possibly devastating effect of even grain-sized meteorites, Oort Belts of from 1012-1015 cometary objects in the plane of the planetary system must be avoided by choosing superecliptic approach trajectories when entering alien stellar systems.2038
  • There is also the possible problem of encountering unnavigable "starfog" in dense galactic gas clouds.2885
  • The danger of running into unbuoyed free-wandering black holes and neutron stars is ever-present.22
17.7 Generation Ships and Suspended Animation  
Generation Ship / Interstellar Ark
stevenspielberg


Citing the tremendous difficulties involved in high speed interstellar journeying, many writers have turned in desperation to the concept of the "generation ship" or "interstellar ark."*

  • These mammoth vessels would contain self-sufficient communities of the sentient spacefaring species and their offspring.2759
  • Farfetched, sophisticated space drives would be unnecessary, since the revolving crew could tolerate trips lasting hundreds of years to the nearer stars.
  • While the original explorer-colonists might never live to see the New World, their great-grandchildren and successive generations would survive to carry the great mission on to its conclusion.
Social and genetic backsliding

Science fiction authors have described the social and genetic backsliding that could occur in such closed ecologies.2794

    • The degree of discipline that each individual would have to accept would be more demanding than that of any present totalitarian regime here on Earth.
    • Birthrates must be strictly controlled, psychological interactions skillfully managed, epidemiological and eugenics rules absolutely enforced.
    • All aberrant ship-threatening behavior severely punished.
    • From the human point of view the restrictions on personal freedom would be well-nigh intolerable.

Still, as Dyson points out, "we have no right to impose our tastes on others."2792


* See especially Bernal,2820 Clarke,2789 Gelula,2790 Haldeman,2839 Heinlein,2854 Macvey,732 Panshin,2579 and Strong.50

Patient extraterrestrial species

The generation ship would provide a pathway
to the stars for any patient extraterrestrial
species that either could not or would not
build relativistic propulsion systems.

The generation ship would provide a pathway to the stars for any patient extraterrestrial species that either could not or would not build relativistic propulsion systems.

  • Speeds from 1-5%c should be ample to commute between neighboring star groups in periods of only a few centuries.
  • This can be done using relatively primitive space hardware.
  • Our own Pioneer 10 probe, which departed the solar system a few years ago, is now heading out into the interstellar void at 0.004%c — a respectable velocity, considering that the craft was designed solely for interplanetary travel.

Of course, during the long journey the technology of the home planet will not stand still. In more than one science fiction story, the crew of the first interstellar ark arrives at their destination only to find that they had been passed many times en route by superior starcraft of more modern design, and that the target system had long since been colonized by others.2791 James G. Strong suggests that "such action will only arouse bitterness among the pioneers, and it would be kinder to avoid their destination — certainly never to come within hailing distance of their ship."50

Like the interstellar ramjet that picks up its fuel
along the way, an "Ark runway" would enable
a generation ship to pick up supplies positioned
earlier across its flight path by unmanned cargo
vessels dispatched from the home planet.
Ark runway

Note that there is no absolute requirement that the full complement of consumables be carried on board the Ark at launch. According to C.A. Cross, "its materials balance could be sustained by the return to it of unmanned vehicles carrying raw materials on long stern chase trajectories."2793  Like the interstellar ramjet that picks up its fuel along the way, an "Ark runway" would enable a generation ship to pick up supplies positioned earlier across its flight path by unmanned cargo vessels dispatched from the home planet.

A problem in biology

Sea voyages of this length were common
among sailors and traders of centuries past:

Magellan’s global circumnavigation required
2 years, Sir Francis Drake’s 3 years, and Marco
Polo’s excursion to China totaled 24 years.
Immortal astronauts

There are several other alternatives to the generation ship.
As Freeman Dyson once remarked:

"Interstellar travel is essentially not a problem in physics or engineering but a problem in biology."

  • For instance, if medical science can learn how to prolong life indefinitely and create immortal astronauts, then the crew which began a lengthy voyage would live to see the end of it.
  • The perspective of immortal beings would doubtless be quite farsighted, and it is not unreasonable to suppose that such creatures would have a leisurely, relaxed outlook on life.
  • A century or two spent out of a 2000 year lifespan would seem no more painful than a 3-7 year voyage would to a human.
  • Sea voyages of this length were common among sailors and traders of centuries past: Magellan’s global circumnavigation required 2 years, Sir Francis Drake’s 3 years, and Marco Polo’s excursion to China totaled 24 years.
Sleeper ship

 
Another possibility is the "sleeper ship," a well-worn science fiction theme during the last half-century.

  • There are basically three classes of sleepers: Ectogenetic astronauts (discussed in the previous chapter), hibernauts, and cryonauts.
  • Hibernauts are starship crew members whose metabolisms have been greatly slowed. Like bears, woodchucks, bats and many rodents, these interstellar travelers would "hibernate" for most of the trip.
  • For starfaring hibernauts, objective centuries would melt into subjective hours, creating a delightful illusion of near-instantaneous travel.
  • Experiments with small mammals here on Earth indicate that it may be possible to induce artificial hibernation in humans using a variety of specific metabolic inhibitors such as the antabolone found in aestivating lungfish.2785
  • The addition of antabolone to other anti-metabolic ingredients should permit metabolism to be reduced to 1% of normal at temperatures near 0 °C.
  • Hibernation for extended periods should be possible, although as in natural hibernation it will probably be necessary to periodically raise the temperature to normal for a few hours each month to allow certain cellular restorative functions to take place.67
Cryonauts

Cryonauts are interstellar travelers whose bodily functions have been entirely shut down. Placed in "suspended animation" at cryogenic temperatures, these starfaring passengers cross the Galaxy in compact, refrigerated vessels equipped with ultrareliable supercomputers designed to patiently wait out the lonely centuries and then automatically reanimate the frozen travelers when the target star system is reached. Robert Prehoda, a science writer and technology forecaster, speculates that:

Cryonauts may travel for many centuries between the stars in fully automatic self-repairing spacecraft controlled by immortal super-computers — descendants of "HAL" in 2001, A Space Odyssey. When they are revived, the journey will seem to have been only one night long. perhaps they will stay alert for a few years to explore new planets and transmit information about them back to Earth. Then they could be frozen again for another mission to a more distant star, repeating the freeze-revive-freeze cycle several times before circling back to Earth after an odyssey of many millenia.67

Suspended animation

Suspended animation will require only a modest-level biotechnology, in all probability.

  • The main problem with freezing organic tissues is the extracellular formation of ice crystals which cause tissue damage, making reanimation impossible.
  • Nevertheless almost every kind of mammalian tissue has already successfully been frozen and thawed under appropriate conditions.3697
  • For instance, rabbit skin has been frozen to -196 °C in liquid nitrogen for 7½ months and is still viable when thawed.2786
  • Successful freezing and thawing of rat pancreas cells down to -196 °C has been shown.2788
  • Rat heart tissue can be reanimated after indefinite storage in liquid nitrogen.1687
  • Low temperature preservation of human blood cells, sperm and ova is now routine.
Whole-organ freezing

 
Whole organs have also been reanimated, though this is more difficult

  • Marshal Shlafer and Armand M. Karow, Jr. successfully restored isolated rat hearts cooled to -30 °C and perfused with a commonly-used biological antifreeze called "dimethylsulfoxide," or DMSO.1685,1692
  • Dr. Isamu Suda of Kobe University in Japan froze a whole cat brain to -20 °C for more than 6 months using a DMSO cryoprotectant perfusate. After thawing, the brain was shown to have nearly normal electroencephalic wave tracings.3694,3695
Whole-body freezing

 
What about whole-body freezing?

  • Many experiments during the past few decades have demonstrated that laboratory rats can be cooled to -10 °C and later restored to life in apparently normal condition.
  • However, the period of "cold sleep" must not exceed a few hours and no more than 50% of the body fluids may be solidified.2787
  • Lower lifeforms are much easier to freeze.
  • Nematode worms, for example, survive suspended animation at liquid nitrogen temperatures indefinitely when subjected to a specific DMSO perfusion treatment.1689
Whole-human freezing

 
What about whole humans?

  • The well-known mammalian diving reflex, together with the body’s lowered oxygen needs at temperatures close to freezing, have permitted people to survive drownings in icy river waters during literally hours of submersion.
  • Dr. Ivan W. Brown, Jr. of Duke University Medical Center has successfully revived a human child whose body-temperature was reduced to 5 °C.67

Following the successful cryopreservation experiments on dog kidneys performed by Dr. M.D. Persidsky at the Institute of Medical Science in San Francisco and Ronald Dietzman of the University of Minnesota, Robert Prehoda has tentatively suggested a hypothetical medical procedure for placing human beings into a state of reversible suspended animation:

The body temperature is lowered to 0° C and a heavy water (D2O) perfusate now circulates through the body. Soon most of the H2O molecules have been replaced with D2O. A 5%-by-volume addition of fluorinated DMSO is now added to the perfusate. This chemical will partially protect the cells during freezing, but its main function is to act as a biological carrier, insuring that the powerful metabolic inhibitors will reach adequate levels within all the cells. Salt-free albumin and ATP are added to the perfusate, allowing the level of dissolved salts within the cells to be reduced. The pressure is greatly increased, and large quantities of dissolved xenon gas begin to be circulated through the body. The fluid-filled cavities around the brain, spinal cord and in the eyes are properly protected by separate perfusion systems.

The heavy-water-based perfusate is replaced with a liquid fluorocarbon which can hold large quantities of dissolved xenon. The pressure is slowly raised as the temperature is reduced. At 5000 psi, an optimum quantity of xenon can be perfused through the body, thoroughly penetrating every cell. No more xenon is needed. The pressure is slowly increased to 30,062 psi. The perfusate pump is shut off. The body temperature is -24 °C. The pressure is then lowered to 5000 psi and rapid solidification begins to take place through the body. Cooling continues as the pressure is again increased to 30,062 psi, allowing the heat of fusion energy to be dissipated. The up-and-down pressure cycle is repeated four more times during continuous cooling, permitting the body to be uniformly frozen. Xenon hydrate protects every cell against freezing damage. The body temperature continues to be lowered at a controlled rate until it is only 4.2 degrees above absolute zero — the temperature of liquid helium.

You are now in a state of complete suspended animation.67

Prehoda estimates that the natural decay of
radioactive isotopes in body tissues will cause
a lethal accumulation of radiation damage
in human cryonauts in roughly 35,000 years.

These steps may be followed in reverse order to achieve reanimation.*

Radioactive isotope decay

 
Cryonauts may not be immortal.

  • Every minute 106 atoms of radioactive K-40 and 2 × 105 atoms of C-14 decay in a human body, spraying bones and organs with beta particles and other low-level radiation.
  • Accumulation of trace amounts of radionuclides is virtually inevitable for any carbon-based lifeform, and these minute natural emissions may produce genetic mutations and other irreversible cellular damage over millennia of cold storage.
  • Prehoda estimates that the natural decay of radioactive isotopes in body tissues will cause a lethal accumulation of radiation damage in human cryonauts in roughly 35,000 years.
  • This difficulty can perhaps be avoided by raising potential astronauts from birth in a carefully controlled radiation-free environment.
  • Food, water, and air must be purified and made free of the harmful isotopes.
  • This accomplished, cryonauts should last for millions of years in suspended animation (assuming adequate shielding from the cosmic ray background) and would be prime candidates for long-term low-velocity galactic exploratory and colonization missions.

Cryonics Societies

* Already about fifty people have been frozen, using somewhat more primitive perfusal techniques, by several Cryonics Societies around the country. These methods may not prove successful, but we won’t know for sure until reanimation is attempted on one of the many frozen patients, perhaps a century from today.

  Chapter 18 ♦ Alien Weapons   
18.0 Alien Weapons
e e smith 360


A weapon makes it
possible to take life
easily and quickly.

War and weapon-making have been an integral part of the millenia of human history on this planet. And yet, it is generally conceded that most of us have strong innate inhibitions against taking the lives of our fellow men. How can these conflicting tendencies be reconciled?

If man hates to kill, why does he?

Dr. Irenaus Eibl-Eibesfeldt, an Austrian-born ethologist at the Max Planck Institute at Munich, has suggested that it is the improved technology of weapons themselves that have made it possible for men to ignore their natural revulsion toward murder. A weapon, he points out, makes it possible to take life easily and quickly; the weaponeer is spared the psychological contradictions of his acts by seeing his target as a mere object.

Death-at-a-distance

In close combat, using primitive weaponry such as spears and knives, the participants are acutely aware of the corporality of their opponents. But weapons technology — mass destruction and death-at-a-distance — has made it possible for combatants to lose that bare thread of empathy that energizes their inhibitions. Weapons technology makes dealing in death an increasingly impersonal affair. As Dr. Eibl-Eibesfeldt observes: "If one asked a bomber pilot to kill his victims one by one, he would be outraged at the suggestion."452

It is not enough to say that superior
technology necessarily breeds
benevolence, since superior technology
here on Earth has often made it easier
for humans to kill.
Surprisingly, there are fairly adequate
defenses for many of them.

However, for reasons that will become
clear in the last section, there appears
to be at least one weapon for which
there is no defense!
In Isaac Asimov’s story
"The Weapon Too Dreadful to Use,"

the aliens in question perfect a means
of severing the link between senses
and brain, thus placing victims in a state
of permanent sensory deprivation.
Warlike intelligences loose in the universe

In view of the above, can we be absolutely certain that technologically superior aliens may not also wield superior weapons? As science fiction authors are fond of pointing out, advanced ETs may have many motivations — conquest among them. It is not enough to say that superior technology necessarily breeds benevolence, since superior technology here on Earth has often made it easier for humans to kill. But even if it turns out that most alien civilizations are benevolent, is it correct thinking to ignore the quite disturbing possibility that there may be a few warlike intelligences loose in the universe?

Worth of study

The worth of a study of alien weapons may be questioned on other grounds. For instance, it may be asked how we can hope to comprehend weapons which are by definition far superior to our own, technologically. But this sort of question ignores entirely the cornerstone of our entire analysis of xenology — the Hypothesis of Mediocrity. There may indeed exist forces and powers wholly beyond present science. If so, we can say nothing about them. All we can do is make the assumption that our science has a grasp of certain basics and proceed accordingly.

We must work with what we have. Turning our backs on the possibility of malevolent aliens will not make the problem go away. In dealing with extraterrestrial intelligences, we must be prepared for both the best and the worst.

Kinds of weapons

 
There are many kinds of weapons that aliens might employ against us.

  • Lasers, "nukes," biological agents, energy absorber fields and disintegrators are the stock in trade of science fictioneers.
  • Authors have suggested psychological warfare, by which the nations of Earth are induced to fight among themselves.
  • In Isaac Asimov’s story "The Weapon Too Dreadful to Use," the aliens in question perfect a means of severing the link between senses and brain, thus placing victims in a state of permanent sensory deprivation.674
  • Larry Niven’s "The Soft Weapon" illustrates what might happen if we were to discover an intelligent alien weapon.607
  • But most weapons fall into one of several categories, as discussed below.

Surprisingly, there are fairly adequate defenses for many of them.
However, for reasons that will become clear in the last section, there appears to be at least one weapon for which there is no defense!

18.1 Chemical, Biochemical, and Biological Weaponry
larry niven 312


Biochemical weapons seem
more subtle, and therefore
more insidious, to most of us.

Explosives are perhaps the most common purely chemical weapon used in modern warfare. Destruction is achieved simply by gross mechanical vibration and demolition. We are probably close to the upper limits of chemical explosives technology, and it is inconceivable that aliens could do much better.

Biochemical weapons seem more subtle, and therefore more insidious, to most of us.

  • For instance, mice have been rendered sterile by the addition of about 30% "heavy" water to their normal drinking water.47 (There are no data for humans as yet.)
  • Or, it has been suggested that if certain items of knowledge can be transferred chemically (as suggested by recent experiments with RNA in rat brains), specific chemicals could be introduced into our environment which would cause fear or passiveness, "suppress intelligence," or "trigger a desired response on a given signal."573

Lethal dosages


  • Lethal chemical agents require milligrams  
  • More powerful toxins require micrograms
  • Bacterial agents require picograms
  • (trillionth’s of grams)

But the most common biochemical weapons fall into two general categories: chemical agents, and biological agents.

Poisons

Poisons are typical chemical agents. Plutonium, for example, is suspected to be highly toxic — as little as 0.3 milligrams assimilated into the body would prove fatal.676

  • However, lethal doses can only be absorbed effectively by inhaling plutonium dust into the lungs, inducing death by cancer.
  • There is relatively little danger of death by ingesting plutonium or its soluble compounds, since the actinides and their chemical brethren aren‘t utilized in human biochemistry in even trace amounts.
  • Because of this, and other material-handling problems, the aliens would have to disperse fifteen grams of plutonium dust over a city for each cancer death they wished to cause, or about ten metric tons for a city of one million inhabitants.676
  • This is about one cubic meter of the stuff.
Nerve gases

Nerve gases are equally dangerous. For instance, VX nerve gas is lethal at about one milligram per person if inhaled;360 when applied to the skin, about five milligrams.398 Hallucinogenic drugs are in the same league, although slightly less toxic. Scanty data available on this subject indicate that the lethal LSD dose may be in the vicinity of ten milligrams or less. Other drugs are less effective. It seems unlikely that ETs would choose this sort of weapon for a mass attack, and although it could be a potent means against individuals, we shall soon see that far more cost-effective weapons are available.

Chemical toxins

The most lethal of the chemical agents are the toxins.
Botulin toxin is often mentioned as one of the most powerful natural poisons known.

  • It is formed by the bacterium Clostridium botulinum, and the lethal dose for humans is about 0.5 micrograms.677
  • This particular toxin produces about 60-70% fatalities, and is extremely resistant to medical treatment.
  • According to a recent United Nations study of the possible effects of biological warfare: "Botulism is … characterized by general weakness, headache, dizziness, double vision, dilation of the pupils, paralysis of the muscles concerned in swallowing, and difficulty of speech. … Symptoms usually appear within twelve to seventy-two hours."678
  • Other toxins are somewhat less dangerous. Batrachotoxin, derived from the skin secretions of the kokoi arrow-poison frog Phyllobates latinasus of the Choco in western Colombia, has a lethality dose of about 10 micrograms per person.
Comparison

 
How do these chemical means compare?

Theoretically, it would take 50 million metric tons
of VX to cover the entire surface of the Earth.

Or about 150 million tons of botulin toxin.
  • Dr. Matthew S. Meselson has estimated that to ensure effectiveness, 100 kilograms of VX per square kilometer must be used, versus 300 kilograms of botulin toxin over the same area.398
  • Theoretically, it would take 50 million metric tons of VX to cover the entire surface of the Earth.
  • Or about 150 million tons of botulin toxin.

This is the best that mere chemical agents can do, and it seems unlikely that aliens would care to synthesize such huge masses of relatively ineffective substances.

Lethal dosages of biological agents

We turn, therefore, to the biological agents.
As pointed out in the United Nations study,

  • Lethal chemical agents are doled out in milligram quantities;
  • For the more powerful toxins, microgram doses are required.
  • But bacterial agents are so effective that lethal dosages are measured in picograms (trillionth’s of grams).678
Reasonably effective treatment exists for
bubonic plague, but not for pneumonic plague.
Studies of the disease in primates indicate
that exposure to as few as 100 bacteria
cause death in about 50% of the animals.

Ten picograms could constitute
a lethal dose for man.
Infectious agents — the plague

 
One of the most vigorous infectious agents is plague.

  • Reasonably effective treatment exists for bubonic plague, but not for pneumonic plague.
  • Studies of the disease in primates indicate that exposure to as few as 100 bacteria cause death in about 50% of the animals.
  • Ten picograms could constitute a lethal dose for man.

To quote again from the U.N. report:

  • A large mass of plague bacteria could be grown and probably lyophilized (freeze-dried) and kept in storage.
  • The agent is highly infectious by the aerosol route, and most populations are completely susceptible.
  • An effective vaccine against this type of disease is not known.
  • Infection might also be transmitted to urban and/or field rodents, and natural foci of plague may be created.678
Anthrax bomb

 
A favorite among science fiction writers a decade or two ago was the "anthrax bomb."

  • Anthrax (Bacillus anthracis) is normally found as a disease in domesticated animals such as sheep, cattle and horses, but most animals are susceptible.
  • It is commonly transmitted to man through the skin, or by ingestion or inhalation of the spores.
  • The inhalation infectious dose for man is estimated variously as from 20,000 — 50,000 spores.
  • Early symptoms occur about one day after exposure, and resemble those of a common cold. Unless there is early treatment with antibiotics immediately, however, death ensues two or three days later in virtually all cases.
Using the most infectious bacteriological agents,
it is estimated that 100 grams per square
kilometer would be sufficient to "disable"
a totally unprotected population of humans.

To infect every person on Earth should require only
50,000 metric tons of, say, pneumonic plague bacteria.
Biological vs. Chemical

 
How do biological weapons compare to chemical agents?

  • Using the most infectious bacteriological agents, it is estimated that 100 grams per square kilometer would be sufficient to "disable" a totally unprotected population of humans.573
  • To infect every person on Earth should require only 50,000 metric tons of, say, pneumonic plague bacteria.
  • This could be accomplished with a fleet of two hundred B-52H Air Force bombers in only ten missions.
  • Such is doubtless the method of choice for malevolent aliens, who could synthesize still more virulent strains of microorganisms with virtually universal resistance to medical treatment.
…a typical swarm of these 6 centimeter-long
insects can contain up to ten billion
individuals, massing 100,000 tons in a cloud
covering some 500 square kilometers.

What if the aliens managed to create
a new breed of insect, extremely vicious
and aggressive? Impossible?
Other "genetic" weapons.

 
There are other "genetic" weapons.

  • Prosserman suggests the following: "A water additive that slowly alters the proportion of male-to-female births in the enemy population, or that amplifies sex-drive, or counteracts population control measures.
  • 'Cloning' could be used...to serially produce a race of 'super-soldiers' from a single individual."573
  • More frightening, perhaps, is the possibility of genetically tampering with animals or rodents,2012 rendering them more prolific and more vicious.
  • But why stop with mammals?2015 According to Stanley Baron in The Desert Locust, a typical swarm of these 6 centimeter-long insects can contain up to ten billion individuals, massing 100,000 tons in a cloud covering some 500 square kilometers. What if the aliens managed to create a new breed of insect, extremely vicious and aggressive? Impossible?
Bees generally do not attack except
in self-defense or to protect the hive.

But "killer bees" are apparently
extremely "nervous."
Africanized killer bees

Maybe not. In 1957, genetics professor Warwick E. Kerr of the School of Medicine of Ribeirao Preto in Sao Paulo, was performing experiments in crossbreeding with African bees. By accident,26 African queens escaped into the Brazilian jungle, carrying their inimical genes with them. In less than a year, a new race of highly aggressive bees arose through in breeding with the common European varieties. Horror stories of these bees attacking humans are legion. In one case, a schoolteacher slapped at her arm when one of the "killer bees" stung her. The insect released an alarm odor. Suddenly, thousands of angry bees engulfed the unfortunate female, and swarmed around anyone who tried to assist her. She died a few hours later.670

It must be pointed out that bees generally do not attack except in self-defense or to protect the hive. But "killer bees" are apparently extremely "nervous." Could not aliens breed an even more aggressive insect?

18.2 Bionic Weaponry
morley safer 315


Electronic Stimulation of the Brain


Normally refers to the implantation of
electrodes deep within a living brain.

In an earlier chapter we discussed various principles of bionics. We examined some of the designs for mechanical bodies which might be utilized by intelligent biological entities. There is no need to cover this ground again here, except to briefly review the possibilities of bionics as weaponry.

Electronic Stimulation of the Brain

Certainly the most widely discussed application of bionic technology is in the field of ESB research. ESB — Electronic Stimulation of the Brain — normally refers to the implantation of electrodes deep within a living brain. These electrodes are pulsed with minute quantities of electrical current in the milliamp range. This interferes with the normal processing of signals by the brain, resulting in altered behavioral patterns.

The military robot may soon be a practical
enterprise even with limited human technology.


Such automata would easily out perform
their biological counterparts, having greater
durability, flexible energy requirements,
and no lack of élan for suicide missions.

In animals other than man, a considerable amount of behavioral control has been achieved.

  • Rats and cats are driven to engorge themselves with food under electrical stimulation, and starving cats have been induced to refrain from eating even though dishes piled high with food were placed before them.495
  • The diameter of the cats‘ pupils can, with suitable electrode implants, be controlled "as if they were the diaphragms of cameras."92
  • A small cat, upon receiving proper stimulation in the tectal area of its brain, willingly attacks a much larger animal. Moreover, it will continue to fight even when clearly outmatched by its adversary.92
  • Female monkeys have been induced to completely lose interest in their young,513
  • Highly aggressive rhesus "bosses" have been rendered docile under ESB.92
  • Dr. Jose M.R. Delgado, one of the leading researchers in the field, dramatically demonstrated the power of ESB more than a decade ago by stopping a charging bull dead in its tracks at the touch of a button. The bull had been "wired" for remote control.484
ESB control of animals

We find that in animals, ESB techniques have been able to control, or at least alter, behaviors of eating, sleeping, aggression, play and sexual activity. But there are also reports of control over motor activity as well.

  • Dr. Lawrence R. Pinneo and his team at the Stanford Research Institute in Menlo Park implanted some thirteen electrodes in the brain stem at the back of a monkey’s head.
  • Small portions of the animal’s motor cortex had been surgically disconnected for the experiment.
  • Pinnec’s device, the Programmed Brain Stimulator, fired the electrodes in the proper sequences to evoke motor responses from the monkey.
  • One programmed sequence, for example, permitted the animal to reach out with its paralyzed arm, grab a piece of food, and return this to its mouth.
  • Another sequence enabled the monkey to reach around and scratch its back, a complicated series of arm and wrist motions.
  • The motor cortex was mapped in more than 200 locations. The experimenters learned exactly which parts of the brain controlled wrist flexion, knee and hip twisting, and grasping movements.516
Applied to humans, ESB has been able to
evoke pain and pleasure, fear, friendliness,
and cooperative attitudes in previously
recalcitrant patients.

Are there any limits to this research?
  • It would appear that full motor control is possible, at least in theory.
Applied to humans

Applied to humans, ESB has been able to evoke pain and pleasure, fear, friendliness, and "cooperative attitudes in previously recalcitrant patients."513 Are there any limits to this research? Delgado, now chairman of the Medical School at the University of Madrid, sees fears of mass control of humans as "fantasies". "ESB may evoke well-organized behavior," he explains, "but it cannot change personal identity."484 He cites two examples to support this position.*

  • First, in all experiments performed to date, researchers have been unable to use ESB to stimulate a male monkey to attack its mate. That is, certain strong inhibitions seem very difficult to overcome.
  • Second, when ESB is used to induce cats to fight one another, it is not a blind, wanton aggression. The attacker carefully sizes up its opponent, selects the best moment at which to strike, and so forth — as in a real fight.
We already know that many primate motor functions
can probably be remote-controlled, at least in theory,
and certain emotional states as well.

It remains to be seen whether ESB techniques can be
extended to mental volitional states as well.
  • It would appear that ESB can alter certain emotional states.
  • What ESB seemingly can not do is alter the subject’s will, except insofar as will is ruled by emotion.

Whether or not alien technologies will find this a fundamental limitation is anyone’s guess. If their ESB technology is vastly superior to ours, they may be capable of surgically implanting electronic stimoceivers in human subjects. We already know that many primate motor functions can probably be remote-controlled, at least in theory, and certain emotional states as well. It remains to be seen whether ESB techniques can be extended to mental volitional states as well.

The possibility of keeping brains alive
outside their bodies has been confirmed
by Dr. Robert J. White of Case Western
Reserve University in Cleveland.

Dr. White has succeeded in keeping several
monkey brains alive in total isolation.

ESB is not the only bionic technology that could be employed by ETs. The state-of-the-art of robot building and prosthetic aids has already been examined. Here I wish only to call attention to the possibility of advanced machine warfare. For instance, the Russians have made no secret of the fact that they are researching the possibility of using disembodied cat brains as control units in air-to-air missiles. The possibility of keeping brains alive outside their bodies has been confirmed by Dr. Robert J. White of Case Western Reserve University in Cleveland. Dr. White has succeeded in keeping several monkey brains alive in total isolation.92

Teleoperators

But brains need not be disembodied to utilize machine technology. Possibilities include such devices as:

  • Hardiman (an artificial exoskeleton worn like a suit of armor).
  • The CAM (Cybernetic Anthropomorphous Machine) electronic horse.
  • The huge biped CAM pedipulator.
  • The proposed fifteen meter high maxipulator — also a biped.

These colossal mechanical "teleoperators" hydraulically multiply the user’s strength and stride by an order of magnitude or more. One is reminded of the giant machines used by the attacking Martians in H.G. Wells’ science fiction classic The War of the Worlds.

The invaders may not wish to risk their own bodies in warfare, even behind the relative safety of a Brobdingnagian automaton.2017 Dr. M.W. Thring, head of the Mechanical Engineering Department of Queen Mary College, University of London, believes that the military robot may soon be a practical enterprise even with limited human technology. In two decades, he claims, we may be able to mass produce robot infantrymen for as little as $10,000 apiece — comparable to the cost of training and equipping a human soldier in a modern army. Such automata would easily out perform their biological counterparts, having greater durability, flexible energy requirements, and no lack of élan for suicide missions.92

There is a fair probability that if we are attacked by hostile ETs, it will be a battle fought exclusively by specialized war machines.2016


* Unnecessary if we implant direct neural taps to sensory and motor lines.

18.3 Sonic Weapons

Figure 18.1 Range of Sound in Air and Water

figure 18 1 500px

Figure 18.2 Sonic Intensityand the Thresholds of Hearing and Pain

figure 18 2 500px
Range of Sound

There are many jobs
for which sonic weapons
are uniquely suited.

Sound, or acoustic radiation, might well be utilized by extraterrestrials against man and his artifacts. Although clearly limited in usefulness by the need for a transmitting medium (Figure 18.1), there are many jobs for which sonic weapons are uniquely suited.

The frequency spectrum for sound is chauvinistically, but conveniently, divided into three general regions — the infrasonic, the sonic, and the ultrasonic.

  • Infrasonic radiation ranges from about 0.001 Hz (cycles per second) for some seismic disturbances up to about 20 Hz.
  • The sonic range, the bounds of human hearing, extends from 20 Hz on up to roughly 20 KHz.
  • Then the ultrasonic takes over, reaching from 20 KHz up to 1 MHz (one million cycles per second) and beyond.

Intensity is measured in dB (decibels)
a logarithmic scale of power pressure
impinging on the ear.

Bioacoustics

A few general aspects of bioacoustics must first be appreciated. Figure 18.2 shows the two most important curves to our analysis.

The first of these is called the threshold of hearing. This is the contour of zero loudness for normal human ears. It is the absolute lower limit of quietness below which we hear nothing.* Note that in the lower sonic range (20-200 Hz) and in the upper sonic range (above 10 KHz), sounds must be considerably more intense for them to become audible than in the middle regions of the spectrum.

The second important curve is called the threshold of pain. Sonic radiation of an intensity greater than this value at any frequency can cause permanent hearing impairment and excruciating physical pain, often described as an uncomfortable tickling sensation in the ears. Certainly, then, aliens could use focused sonic beams to quickly deafen their victims with an agonizingly painful blast of audible sound.

Invisible weapon

But to leave it at this is to miss the most frightening aspect of sonic weapons. Compare the two threshold curves. The pain curve lies below the audibility curve for both infrasonic and ultrasonic frequencies. Beams of acoustic radiation of these kinds could be virtually undetectable by our ears, and yet carry an intensity well above our pain threshold. Here we have an "invisible" weapon, a force which can severely affect us physiologically — yet we are unable to hear it. The specific effects of various frequencies differ, and we take this up next.

Here we have an "invisible" weapon, a force
which can severely affect us physiologically
— yet we are unable to hear it.

Although research in infrasonics is surprisingly scanty, one important conclusion has definitely emerged: Subsonics can affect humans adversely. Infrasound is felt rather than heard, and has the potential of shaking bodies and buildings to pieces at high intensities.

Infrasound exposure

 
But what are the usual symptoms of human exposure?2152

  • At relatively low power levels (about 120 dB) subjects report chest vibration, throat pressure and interference with respiration, and visual field vibration.431
  • Whole body mechanical vibration is very common.628
  • There are reports that emotional states may suffer some alteration under the influence of low intensity waves.
  • It is entirely possible that fear may be induced,537 or psychological depression.432
Pronounced effects at higher intensities

 
At higher intensities, the effects are far more pronounced.

  • Vladimir Gavreau, head of the Electroacoustics Laboratories of CNRS in Marseilles, France, relates that five minutes, exposure to 200 Hz at 160 dB caused painful and intense frictional rubbing of his internal organs, resonating with the sound.
  • The accidental exposure was described as "almost lethal" by one researcher,448
  • Apparently the resulting pain took days to fully abate.
  • Had they remained in the sonic fluence for another few minutes, there would almost certainly have been severe internal hemorrhaging, followed by death.
Symptoms of 150 dB at 50-100 Hz

An Air Force study in the early 1960s tested subjects at power levels of 150 dB using frequencies of 50-100 Hz.
The following symptoms were reported:431

  • coughing
  • choking respiration
  • pain on swallowing
  • headaches
  • loss of visual acuity and giddiness
  • severe substernal pressure
  • gagging
  • tingling sensations

Table 18.1 Effects of Mechanical Vibration on Man628

table 18 1 effects of mechanical vibration on man 400
Effects of Mechanical Vibration

Lower frequencies seem to be most energy-efficient in eliciting disabling symptoms from the human organism (Table 18.1). Research in the subsonic range 2-20 Hz indicates the following:

  • Intensities as low as 120 dB cause dizziness, feelings of lethargy and general lack of control.448
  • At 150 dB there is intense discomfort related to the organs of balance, causing nausea, a sensation of rotating, and involuntary movement of the eyeballs.622
  • General disequilibrium, disorientation, lassitude and weakness, and blurring of vision are also common.628

It would seem that high-intensity "subsonic stunners" postulated in various science fiction tales are a practical possibility.231

Infrasonic and low sonic radiation can also
cause massive structural damage …

as in the famous case of the Tacoma Narrows
Bridge
at Puget Sound, Washington, in 1940.
Infrasonic radiation surrounds us all the time.
Infrasound cannot be stopped by any normal
building material, walls, or acoustic absorbers,
since its wavelength is too long.

Infrasonic and low sonic radiation can also cause massive structural damage. The resonant modes of vibration for bridges, buildings and cars range from 10-100 Hz. Destruction occurs when a standing wave arises along one vibrational mode of the structure. At this resonant frequency the waves are virtually undamped and can build rapidly to a critical level — as in the famous case of the Tacoma Narrows Bridge at Puget Sound, Washington, in 1940.

Infrasonic radiation surrounds us all the time. "Quiet" automobiles traveling at the speed limit commonly put out more than 100 dB in this range. Infrasound cannot be stopped by any normal building material, walls, or acoustic absorbers, since its wavelength is too long.

Gavreau has already constructed several alarmingly powerful "sonic guns."

  • One such device is capable of emitting two kilowatts of power at 37 Hz. It has never been run at full power, since even at low levels the ceiling begins to crack and major body resonances are set up.
  • Gavreau is reportedly now at work on the problem of building highly directional sonic projectors; for instance, an organ-pipe device 24 meters in length designed to operate at 3.5 Hz.628
  • He has estimated that large sonic cannon more than seven meters in diameter could now be constructed with power outputs close to the theoretical maximum for air — roughly 200 dB.448 Can the aliens be far behind?

But let’s not ignore the opposite end of the sonic spectrum. Medical studies have shown that although ultrasonic radiation has more effect on the white matter in the brain than on the grey matter (the cerebral cortex), most neural components can be destroyed in a given region "without interrupting the blood vessels in the same region."623 Only a very detailed autopsy could reveal the true cause of death.

Other than effects on hearing acuity, however, the primary biological consequence of ultrasonic irradiation is vibrational heating.

Present human technology has been able to
produce focused ultrasonic radiation, using
a curved radiator, of more than 190 dB.

That is, we‘ve already nearly attained
the theoretical upper limit, and the effects
are well known to us.
  • It is well-known that heat resulting from 20 KHz at 150-160 dB is quite sufficient to kill small animals.
  • But apparently the presence of fur serves to absorb this radiation, and shaven animals fare much better.
  • Men exposed to 150 dB were not significantly affected in one study.627
  • But it has been reliably estimated that 180 dB of airborne ultrasound would constitute a lethal dose for humans.

Would ETs select an ultrasonic weapon? It’s doubtful. Present human technology has been able to produce focused ultrasonic radiation, using a curved radiator, of more than 190 dB. That is, we‘ve already nearly attained the theoretical upper limit, and the effects are well known to us. And as we shall see in the next section, there are much more efficient ways to cause thermal destruction, techniques not nearly so range-restricted and medium-restricted as ultrasound.


Intensity measured in dB (decibels)

* Intensity is measured in dB (decibels), a logarithmic scale of power pressure impinging on the ear.

  • 30 dB is considered very quiet.
  • Normal conversation takes place at about 60 dB.
  • Driving diesel trucks or motorcycles exposes one to about 85-90 dB.
  • Rock concerts may reach 110 dB or higher.
18.4 Photonic Radiative Weaponry
Electromagnetic radiative weaponry

Table 18.2 The Electromagnetic Spectrum

table 18 2 electromagnetic spectrum 500

Two varieties of radiative weaponry:


■ Electromagnetic (photonic)
■ Particulate (atomic and nuclear particles)

Radiative weapons are comprised of the class of devices which achieve their deadly results by the use of projected radiation — acoustic radiation is usually excluded from this category. There are two varieties of radiative weaponry: electromagnetic (photonic) and particulate (atomic and nuclear particles). We‘ll look first at the electromagnetic ones (Table 18.2).

Static fields

Static fields need be considered only briefly. There is little or no evidence that mere electrostatic or magnetostatic fields have any effect whatsoever on the human organism. No gross effects have been observed in tests of laboratory animals subjected to magnetic fields up to several kilo-gauss.568 Likewise, few significant effects are reported from exposures to time-invariant electric fields. Hence, we find that static fields won‘t be useful to aliens as weapons.

Very Low Frequency

VLF (Very Low Frequency) radiation has long been considered virtually harmless. It is emitted, for example, by power lines and electrical appliances we use every day. How could VLF possibly be harmful?

There are several interesting effects produced by exposure to slowly oscillating magnetic fields, such as the magnetic phosphene.566 The French physicist d'Arsonval was the first to describe these colorless "shimmering luminosities" in the last century. Application of VLF frequencies of from 10-100 Hz to the head causes these flickering phosphenes to appear at the borders of the visual field.568 Could ETs make us think we see ghosts?

  • Muscle contractions have also been induced in frog tissue by VLF radiation.
  • Furthermore, a study conducted in the Soviet Union a few years ago concluded that exposures to 50-100 volts per centimeter have significant effects on humans. Subjects reported tremors in arms and legs, slowed heartbeat, fatigue and sleepiness,570 and even anemia.679
  • Recent Navy research has demonstrated that an electrical field at 60 Hz can alter the concentration of fats in the human bloodstream.463
  • And according to the late Dr. Norbert Weiner, a 10 Hz ambient electrical field causes "unpleasant sensations."526 The oscillating field coincides roughly with the brain’s alpha-rhythm frequency.
  • A variation of this technique, using scalp electrodes, is used to put human subjects to sleep — the so-called "Russian sleep machine" or "electrosleep."
Humans relatively immune

But these findings are hotly contested by Dr. Otto H. Schmitt, Chairman of the Biophysics Group at the University of Minnesota. He recently completed a two-year study to determine whether or not man can detect VLF magnetic fields. Schmitt found that not one of his 500 subjects could consistently tell when the field was on or off. "Humans are relatively immune even to strong magnetic fields," he writes, "so long as they are not shocked, burned, or grossly polarized by the fields."629 He points out, however, that persons with prosthetic or bionic equipment (such as a pace-maker implant for the heart) might be particularly susceptible even to relatively low intensity VLF fields.

Schmitt found that not one of his 500 subjects
could consistently tell when the field was on or off.

"Humans are relatively immune even to strong
magnetic fields," he writes, "so long as they are not
shocked, burned, or grossly polarized by the fields."
Inconclusive data

Accordingly, we can only note that at present the data are inconclusive. If it turns out that VLF is harmful after all, it’s a fair bet the aliens will know about it too!

Inductive heating

Of course, we have been discussing using VLF against humans directly. But aliens could build giant inductors and utilize the well-known principle of inductive heating on any metallic object, such as cars and spaceships.548 Inductors use frequencies from 10 Hz up to 1 MHz, the former allowing uniform volume heating and the latter causing mere skin heating. A one-megawatt inductor weapon should be capable of raising one ton of metal about two degrees Celsius every second.*


* Such a weapon would require only two hours to raise an Apollo command module to red heat. The craft would reach its melting point four hours after heating began, and would be reduced to a spherical molten mass about ten minutes later.

Radio wave, microwave and infrared

Radio wave, microwave and infrared effects are manifested primarily as simple radiative heating.

  • The longer radio waves cause thermal agitation and rotation of molecules, resulting in a rise in temperature of the bulk material subjected to irradiation.
  • Microwave and infrared, on the other hand, stimulate molecules in what are called vibrational modes.
  • Both infrared and visible radiation act on the whole molecule, causing direct heating. But the ultimate result is essentially the same — increased temperature.
  • As far as specific destructive power is concerned, suffice it to say that a narrow beam of such radiation could burn a hole through a human with only a few tens of kilojoules of energy.
Infrared and lower-energy forms


 Infrared and lower-energy forms of electromagnetic radiation are known collectively as nonionizing radiation.

  • Such radiation doesn‘t really alter the electronic state of the molecules themselves, but merely shakes them up a bit.
  • It has been shown that nonionizing radiation doesn‘t cause genetic damage.
  • Fruit flies tested under kilowatt Hertzian radiation for 12 hours evidenced no mutational changes whatsoever.680
Visible and ultraviolet light


 Visible and ultraviolet light are considered to be slightly more "penetrating" forms of radiation.

  • These photons are absorbed by the orbital electrons of atoms, but the energy thus absorbed is sometimes insufficient to knock the electrons clear of the atom.
  • The excited but unionized atom is still plenty reactive, bringing about the production of deadly photo-products such as hydrogen peroxide in surface cells.
  • UV is selectively absorbed by nucleic acids and proteins, and the mutagenic effects of UV bring on skin cancer.
  • Exposures to as little as 600 joules over a naked human body causes surface cells to perish, "not only due to the disruption of nucleic acid synthesis, but also due to damage to the fine structures and disturbance of metabolism."445
X-rays and gamma rays


 As we move to still higher energy radiation, we enter the realm of X-rays and gamma rays.

  • The activities of such radiations are not confined merely to the surface, but are instead deeply penetrating. These are called ionizing radiations.
  • Photons of large energy are absorbed by orbital electrons but, unlike visible or some UV radiation, these electrons are hurled from the atom, leaving behind a charged ion. Such ionized atoms are extremely reactive chemically.
  • The biochemical effects appear only after a period of latency, usually a few days or weeks.
  • Radiosensitivity is marked in cells with high metabolism and high reproductive rates.604
  • Lethality doses for man run approximately one kilojoule for X-rays (1.5 × 1017 photons/m2)
  • Lethal dose of three kilojoules for "soft" gamma radiation (2 × 1015 photons/m2).379
An object a few megameters away,
even if in Earth-orbit, could easily
evade detection indefinitely.

Farther out than that, and our chances
of detecting the intruder are virtually zero.

The far greater difficulty of picking up
a distant target whose location and even
existence are uncertain, and which is
designed to be non-reflective, should
be obvious.
Radar

How can electromagnetics be applied to the science of weaponry? The earliest use was the invention of radar. It’s generally assumed that if an alien spacecraft were to approach Earth without warning, our Ballistic Missile Early Warning System (BMEWS/SAGE) could not fail to pick it up. This is a gross misconception. In addition to the fact that the SAGE computers are specifically programmed to ignore any nonballistic UFO-like targets, our radars are only effective out to a few hundred kilometers, at best. An object a few megameters away, even if in Earth-orbit, could easily evade detection indefinitely. Farther out than that, and our chances of detecting the intruder are virtually zero. As Robert Salkeld points out in War and Space, it took the better part of a month for Earth-based observatories to locate and detect laser echoes from the specially-designed Apollo 11 reflector left behind on the surface of the Moon. Salkeld laments: "The far greater difficulty of picking up a distant target whose location and even existence are uncertain, and which is designed to be non-reflective, should be obvious."561 A surprise attack from space is therefore quite possible.

Lasers

Satellite blinders

But certainly the most alarming photonic weapons technology is the military laser. A bewildering array of possibilities has suddenly become available. For instance, it’s well known that to gaze into a laser beam of even low intensity can cause permanent blindness. It has been suggested that "satellite blinders" could be placed in orbit by aliens. Anyone who glanced at the sky for more than a few moments would become permanently and irreparably blind. Arthur C. Clarke uses a variation of this idea in his short story "The Light of Darkness."637

The CIA developed an apparatus which fired a
tiny pencil of laser light at a closed window.

Vibrations of the air inside the room — due to
people talking — set the window pane vibrating.

This in turn caused minute fluctuations in the
reflected laser beam which could be decoded
and reassembled back into the original speech,
at the receiver!
The big breakthrough in high-power laser
technology occurred when it was discovered
that fast-flowing reactive gases could be
chemically combined rapidly, releasing huge
quantities of laser energy.
Laser listening device

Another unusual application is the laser listening device. Victor Marchetti and John D. Marks, in their collaboration The CIA and the Cult of Intelligence, relate that in the early 1960s the CIA developed an apparatus which fired a tiny pencil of laser light at a closed window. Vibrations of the air inside the room — due to people talking — set the window pane vibrating. This in turn caused minute fluctuations in the reflected laser beam which could be decoded and reassembled back into the original speech, at the receiver! Although the contrivance apparently had a few technical bugs, the idea of spying on a nearby alien spacecraft — in windless, airless space — is intriguing.

Defense satellites

The Pentagon is now examining the possibility of placing a network of "defense" satellites in orbit, each armed with powerful lasers. These orbital robots would approach and destroy "alien" hardware, or disable missiles that flew within range. The Soviets are reportedly working on a satellite-killer of their own.

Laser cannons

This brings us to the "big daddy" of laser weaponry, the so-called laser cannons. The big breakthrough in high-power laser technology occurred when it was discovered that fast-flowing reactive gases could be chemically combined rapidly, releasing huge quantities of laser energy. The Gas Dynamic Laser (GDL), one of the major contenders in the high-power sweepstakes, produces a concentrated beam of laser light when its reaction gases are combined and forced through tiny nozzles at supersonic speeds.

It’s believed that prototype laser cannons will be available in the 1978-1979 period, and that working field models may be coming into use in the early 1980's.461 Already the U.S. Army has fielded an experimental laser tank, called the Mobile Test Unit (MTU). From early in 1975, the MTU has been tested at the Redstone Arsenal in Huntsville, Alabama. The driver rides in front, aiming the turret in the rear at the desired target. The Electric Discharge Laser (EDL) in the turret fires a multi-kilojoule pulse, powerful enough to burn holes in wood, metal, or human flesh. Says a researcher on the MTU development team: "It‘ll go right through you right now with no trouble."392

Semi-portable laser rifle.
Designed to be carried and operated
by three men, this high-energy chemical
laser is aimed like a shotgun and fired.

It is supposedly capable of burning a
centimeter-wide hole in an unprotected
human body at a range of up to 8 km.

"Once you‘ve got him in your sights,"
says one TRW engineer, "you‘ve got him.
There are no misses."
Laser rifle

There is also under development, by TRW Systems in Redondo Beach, California, a semi-portable laser rifle.

  • Designed to be carried and operated by three men, this high-energy chemical laser is aimed like a shotgun and fired.
  • It is supposedly capable of burning a centimeter-wide hole in an unprotected human body at a range of up to eight kilometers.
  • "Once you‘ve got him in your sights," says one TRW engineer, "you‘ve got him. There are no misses."394
Continuous-operation laser
  • As for gross power and destructive capability, Avco has reported that its eight kilowatt continuous-operation laser cuts through Plexiglas at about 2.5 cm per second.527
  • The twenty kilowatt laser at the Air Force Avionics Laboratory near Dayton, Ohio, is capable of burning three centimeter wide holes in firebrick at the rate of 10 cm per second.
  • It’s also known that the Air Force has since constructed GDLs capable of several hundred thousand kilowatts of contiuous power, although the exact details remain classified.397
  • Dr. J. Paul Robinson at Los Alarnos speaks matter-of-factly about orbiting megajoule lasers in the near future.410
  • It is a fact that the Pentagon spent nearly $200 million in Fiscal 1976 on laser weapons technology alone.
High frequency lasers

High frequency lasers haven‘t actually been constructed as yet, but it has been emphasized repeatedly that both X-ray lasers491 and gamma ray lasers, called grasers,475, 506 are theoretically possible. Even though practical feasibility has not been demonstrated, many scientists are already predicting that when x-ray lasers are constructed, energy fluxes "greater than one kilojoule per square centimeter" will be available.507

Death rays


 Admittedly, laser "death rays" have their limitations.

  • Since light travels in a straight line, beams cannot be aimed at anything below the horizon unless orbital mirrors are used.
  • Furthermore, laser light is scattered or absorbed by clouds, mist, dust, fog, and smoke.
  • If the target is shiny and reflective, most of the laser’s energy can be dissipated harmlessly.

And yet it’s still considered a very promising weapon.

  • It fires high-energy "projectiles" that travel at the speed of light.
  • Aiming is vastly improved.
  • Were lasers to be used in space battles, where beams can travel thousands of kilometers uninterrupted to their targets, it would represent a formidable weapon indeed. Our extraterrestrial invaders will surely be aware of this.
Other photonic weapons

Focused solar radiation as an offensive weapon.
This idea is really quite old. In fact, the great
Greek mathematician Archimedes was the first
to have actually put the plan to practice.

Between 215 and 212 B.C., the Roman navy
beseiged the Hellenic port of Syracuse.
Archimedes set fire to the fleet by using
polished reflectors to concentrate the Sun’s
heat onto the attackers.
It’s theoretically possible, to orbit giant mirrors
in space, to hover over the Equator and to
reflect sunlight to any spot on Earth.

And as they need only be made of mylar film
coated with a few atoms' thickness of aluminum,
they would be extremely light even if they were
miles on a side.

It would be technically feasible to erect
such mirrors using Saturn V launch vehicles.
Focused solar radiation

Two other photonic weapons deserve at least a passing mention. The first of these is the idea of using focused solar radiation as an offensive weapon. This idea is really quite old. In fact, the great Greek mathematician Archimedes was the first — to the best of my knowledge — to have actually put the plan to practice. Between 215 and 212 B.C., the Roman navy beseiged the Hellenic port of Syracuse. Archimedes set fire to the fleet by using polished reflectors* to concentrate the Sun’s heat onto the attackers.

In 1969 Dr. Thomas O. Paine, a former administrator for NASA, suggested that it might be possible to place a giant solar reflecting mirror on the lunar surface. This mirror, he claimed, could be used to destroy any chosen city on Earth.77 Arthur C. Clarke has hinted that such a weapon might be wielded from Earth-orbit. "It’s theoretically possible," he asserts, "to orbit giant mirrors in space, to hover over the Equator and to reflect sunlight to any spot on Earth. And as they need only be made of mylar film coated with a few atoms' thickness of aluminum, they would be extremely light even if they were miles on a side. It would be technically feasible to erect such mirrors using Saturn V launch vehicles …"81

Invisibility cloak

The second photonic device is the practical invisibility cloak. It is often pointed out that an invisible man would also be quite blind.53 I can see no easy way around this fundamental objection. However, what if aliens wished merely to render isolated structures invisible? One suggestion along these lines entails the erection of a hemispherical cap over the buildings. The outer surface of this cap would consist of a 3-D holographic "picture" of the virgin terrain prior to the construction of said building. In this case, the ETs wouldn‘t particularly care whether or not they could see out from their hideout, as they could place TV cameras outside the periphery of the cloak. Or, if it is possible to maintain a radial refractive index gradient around the buildings, a kind of spherical lens might be created. The resulting image of the refracted background should be at least as good as a fine mirage, and perhaps even better — using advanced alien technology.

Subjective invisibility

And of course we can always resolve the optics problem by resorting to subjective invisibility. That is, the alien causes humans to simply ignore his presence, psychologically. For all practical purposes, the ET would have become "invisible."55 An interesting variation on this theme may be found in Larry Niven’s science fiction novel A Gift From Earth (Matt Keller’s "Plateau Eyes".231


* coppered shields, about a hundred of them trained on each enemy vessel.

18.5 Particulate Radiative Weaponry
Effects of particulate radiation

How does particulate radiation affect the human organism? One most unusual effect relates to visual sensations caused by the passage of fast-moving particles through the retina. It has been reported that about 10% of all relativistic nitrogen nuclei shot through a human eyeball are perceived as tiny streaks of light in the visual field.473 High energy muons and pions have been found to cause a similar phenomenon, appearing as a crescent-shaped flash as large as one-half the entire field of view.529

But by and large, the biological effects of particulate radiation are quite straightforward.

  • Any particle bearing an electric charge (protons, electrons) and having a reasonably high kinetic energy will interact strongly with the orbital electrons in any physical medium it passes through.
  • Charged particles lose energy to orbital electrons bit by bit as they pass, unlike photons which divest all their energy in a single blast.
  • Neutral particles like the neutron cannot interact electromagnetically with matter, and zip right past the orbital electrons.
  • All their energy is transferred in a single collision with an atomic nucleus — which absorbs them and recoils violently.
Ionizing / nonionizing radiation
  • We call high-energy charged particles directly ionizing radiation.
  • Whereas photons of very high energy and neutrons of all energies are referred to as indirectly ionizing radiation.
  • Slow moving charged particles and low-energy photons are known collectively as nonionizing radiation.
Nuclear particle zoo

At last count, well over
200 different particles
had been discovered.

Which of the particles in the "nuclear particle zoo" are germane to our study? At last count, well over 200 different particles had been discovered. Let us briefly consider just a few of them.

  • We've already mentioned the proton (positive charge) and the neutron (neutral) — the constituents of atomic nuclei — and electrons (negative charge).
  • Each of these has its antiparticle. An antiparticle is the "opposite" of a particle, in the sense that when the two come together they are observed to undergo annihilation (mutual destruction) and release large quantities of energy.
The anti-particles
  • The anti-electron, the first antiparticle to be discovered, was given a special name — the positron.
  • The positron-electron annihilation reaction is very specific; positrons would presumably be stable in a universe without electrons.681
  • The proton and neutron each have their anti counterparts.
  • However, they are slightly less specific in their reactions. An antiproton will annihilate both a neutron and a proton; likewise, the antineutron annihilates both neutrons and protons.681
Pions
  • Pions are particles which come in three varieties — positive, neutral, and negatively charged.
  • They are produced via proton-antiproton and neutron-antineutron reactions, and also in cases where protons or neutrons collide with nucleons in normal matter.
  • But pions are unstable, decaying to muons and electrons in very brief times.
  • Muons exist in positive and negative forms and are also unstable, decaying in about two microseconds to electrons and other particles.

Let us turn now to applications.

Thunderbolts

The taser

The most common form of electron transfer in our everyday lives is via electricity. Can this be used as a weapon? Dr. John Cover, a scientist in Newport Beach, has developed a device he calls a taser. The taser passes a jolt of electricity at 50,000 volts (but very low current) through the body, temporarily freezing the skeletal muscles with few lasting effects. This "stun gun" is being manufactured and marketed under the trade name Taser Public Defender by Advanced Chemical Technology, a Los Angeles firm.

One of the larger artificial lightning
machines was the one built for
the 1939 World’s Fair in New York.

Its output reportedly exceeded ten million
volts at about 200 kilojoules per bolt.

This is sufficient to jump more than
ten meters through dry air.

But this device gets the energy to the human target by firing tiny darts attached to ten meter threadlike wires. Surely there must be a better way!

Thunderbolts

The alien attackers may be capable of actually throwing thunderbolts at us, those powerful instruments of Zeus' arbitrary whim.

  • One of the larger artificial lightning machines was the one built for the 1939 World’s Fair in New York. Its output reportedly exceeded ten million volts at about 200 kilojoules per bolt. This is sufficient to jump more than ten meters through dry air.
  • Voltages of more than twenty million volts are commercially available today.
Natural lightning

 
Natural lightning is even more impressive.

Natural lightning is even more impressive.
Discharges from so-called "positive giants"
pass energies in excess of several billion
joules, at hundreds of millions of volts
electrical potential.

The cores of such strokes momentarily reach
temperatures of up to 30,000 °C, several
times hotter than the solar photosphere.
  • Discharges from so-called "positive giants" pass energies in excess of several billion joules, at hundreds of millions of volts electrical potential.
  • The cores of such strokes momentarily reach temperatures of up to 30,000 °C, several times hotter than the solar photosphere.
  • It's quite possible that hovering alien spacecraft could use a weapon of this kind to destroy houses, vehicles, or even crowds or single individuals.
  • A tight beam of ionizing radiation might precede the bolt to the ground, ionizing an easy conduction path in air straight to the target.
  • It would be difficult to operate a hand-held device of this kind, such as a lightning bolt rifle, as it would be virtually impossible for the attacker to avoid being shocked himself.
Since ball lightning requires no ionized
path and appears to be self-sustaining,
it should be possible for ETs to wield
portable kugeiblitz projectors.

A person directly hit with one of these
plasma balls could suffer severe radiation
burns, electrocution, and traumatic shock.

There is a small problem with aiming
accuracy, as the motions of the glowing
balls are frequently erratic.

However, there have been many reports
of ball lightning actually "chasing" people,
apparently attracted to a small
accumulated net charge.

Aim may in fact be a nonproblem after all.
Other forms of lightning

Of course, there are other forms of lightning. Of particular interest is the phenomenon known as ball lightning.

  • After decades of controversy, it is now generally accepted that these fiery balls of electrical energy — kugelblitz — do exist.
  • They are described as being anywhere from one centimeter to one meter in diameter, in colors ranging from white and blue to red and yellow.459
  • The plasma globes can be spherical or elliptical in shape.466
  • Lifetimes are typically about five seconds, but occasionally a kugeiblitz has been seen to remain intact for more than a minute.
  • Their demise occurs in one of two ways — silently (fast or slow), or explosively with a loud pop — and they generally travel at about 4 meters per second, either vertically611 or horizontally.459
How much energy?


 How much energy do they contain?

  • One 20 centimeter kugeiblitz fell into a small barrel of water, causing it to boil for several minutes.549
  • Another plasma ball was seen entering a heavy oak piling, which shattered violently moments later.
  • The ball was estimated to contain an energy of 100 kilojoules.610
  • Energy densities have been variously estimated from 20 megajoules per cubic meter611 up to 100 megajoules per cubic meter.505
  • One author has speculated that persons standing within a meter or two of a large lightning ball might well be exposed to radiation sufficient to cause radionecrosis, although the balls are rarely reported to emit heat.505
Portable kugeiblitz projectors

Since ball lightning requires no ionized path and appears to be self-sustaining, it should be possible for ETs to wield portable kugeiblitz projectors.

  • A person directly hit with one of these plasma balls could suffer severe radiation burns, electrocution, and traumatic shock.
  • There is a small problem with aiming accuracy, as the motions of the glowing balls are frequently erratic.
  • However, there have been many reports of ball lightning actually "chasing" people, apparently attracted to a small accumulated net charge.466
  • Aim may in fact be a nonproblem after all.
Torch weapons

The problem with charged particle torches in general
is that there’s an obvious defense available.

Electrostatic screens …

Only if torch weapons aren’t expected would
the torchers have a fighting chance for success.

Electrons in space


 Electrons can be utilized more directly in space.

  • A beam of electrons could be fired at the hull of an alien spacecraft, embedding negative charges throughout its bulk.
  • The craft might then be grappled electrostatically — a tractor beam of sorts.
  • Unfortunately, the forces generated are quite weak over normal operational distances, and the skin charge would be easy to neutralize by the aliens themselves.
Muon torch


 More reasonable, perhaps, are the torch weapons. The muon torch is a prime example.

  • Muons are very inert mesons, so inert that they comprise about 80% of the cosmic rays at sea level and have been detected in mines, hundreds of meters beneath solid rock.681
  • The depth of penetration depends almost solely upon the initial energy of the beam of particles — the higher the energy, the farther they go.
  • But muons decay after 2.2 microseconds. We can arrange the beam energy so that, after the muons have traveled, say, one kilometer, the decay time has elapsed.
  • One kilometer from the source, then, the particles in the beam will suddenly decay, releasing their energy with almost pinpoint accuracy.
  • Range can be adjusted on the muon torch by merely adjusting the energy of the beam.

Table 18.3 Range of the Charged-Pion Torch in Vacuum

table 18 3 range of charged pion torch 400
Charged pions torch

Charged pions can also provide us with a torch effect. However, since charged pions decay in only 0.03 microseconds, to get the same range pions must be accelerated to energies about ten thousand times higher than muons (Table 18.3). But the pion torch is superior for one simple reason.

  • When the muon decays, most of the energy thus liberated is carried away by neutrinos and is effectively lost.
  • But when the pion decays, its full rest mass energy of 139 MeV is delivered to the target.
  • If the aliens have constructed a pion torch capable of delivering a pion current of one milliampere — not inconceivable using modern human technology — the weapon would have a power at the target of about 150 kilowatts.*
Defense against
  • The problem with charged particle torches in general is that there’s an obvious defense available.
  • Electrostatic screens around an enemy ship in space would repell the pions as easily as electrons are deflected in a TV picture tube.
  • Only if torch weapons aren’t expected would the torchers have a fighting chance for success.
Neutral pions
  • Neutral pions are available too, of course, and would be quite undeflectable by any electrical field.
  • There would be no elegant defense against a neutral pion torch.
  • There’s just one catch. The neutral pion decays in 10-15 seconds.
  • To achieve the same range as a charged pion torch, energies must be some seven orders of magnitude greater.
  • Even at the terrific energy of 1000 TeV, at least three orders of magnitude above the capacity of the largest accelerator on Earth, the neutral pions would have a range in vacuum of only 2.2 meters.

* Note also that the pion decay cloud could be materialized inside the enemy ship, incinerating everything within but leaving the hull intact.

Antimatter

Figure 18.3 The Starship Enterprise fires its phasers

Pure antimatter

We have not yet exhausted the list of nonphotonic radiative weapons. It has long been believed by many nuclear physicists that whole atoms of antiparticles could be built up — into anti-atoms.

A mere 64 grams of antimatter,
released on the surface of this
planet, would provide an
explosive yield of one megaton


 — the approximate energy
requirement to utterly destroy
a city of one million inhabitants.

  • An atom of antimatter would have a negatively charged nucleus surrounded by a cloud of positrons.
  • Recent research has revealed the first synthesis of the anti-helium-3 nucleus,487 and the antideuteron (anti-deuterium nucleus) has been known for a decade.
  • It is not inconceivable that ETs may be able to fashion macroscopic chunks of pure antimatter, stored temporarily in some kind of (perhaps) magnetic confinement vessel.

A mere 64 grams of antimatter, released on the surface of this planet, would provide an explosive yield of one megaton — the approximate energy requirement to utterly destroy a city of one million inhabitants.573

Other applications for antimatter


 Other applications for antimatter may be imagined.

  • A cloud of anti-plasma released at an enemy vessel in space could cause severe structural weakening of the hull, as in the original-series Star Trek adventure "Balance of Terror" and other science fiction tales.607
  • Another possibility is the use of antiparticle beams to slice up chunks of ordinary matter.
  • A beam of anti-protons, for instance, would cut right through a distant spacecraft.
  • Not only would the ship be physically riven in two, but fierce radiation accompanying the annihilation reactions would undoubtedly prove quite deadly to the occupants.

Aliens would be smart enough not to choose antiprotons for this purpose, however, as these are susceptible to electrostatic defenses. ETs would use antineutrons instead. Or they may use other forms of beam weapons that we not yet imagined (Figure 18.3).

18.6 Nuclear Explosives

Table 18.4 Thermonuclear Explosive Blast Effects

table 18 4 thermonuclear explosive blast effects 400

3000 gigatons to kill
half the human race.

Nuclear explosives don‘t fit neatly into the above categories, for the simple reason that the blast products consist of virtually every brand of destructiveness discussed so far.

  • About half of the energy of a thermonuclear device comes off as sonic energy, in the form of high pressure shock waves and gross mechanical vibration.
  • The other half consists of electromagnetic radiation of all kinds, primarily x-rays but including ultraviolet, visible and radio emissions.
  • Nuclear radiation, primarily fast neutrons, constitute a few percent of the total.
  • Fallout comprises various amounts of poisonous radiochemicals.
  • Nuclear weapons are very messy affairs.
  • Many fires are started at once by the flash of an H-bomb.
  • The majority of casualties result, not from the effects of the blast itself, but by the firestorm sweeping the victim city.
  • Only at the very outermost edges of the hellish thermal maelstrom are individuals able to drag themselves to safety (Table 18.4).
Nuclear weapons out in space

 
Out in space where there is no atmosphere to absorb and scatter radiation, the destructive range is vastly increased.

  • It has been estimated that a 20 megaton thermonuclear device would be sufficient to kill astronauts in unshielded spacecraft within a sphere nearly 1000 kilometers in diameter.
  • A lethal sphere the size of the Earth itself would require a 10,000 megaton bomb, "a weapon which probably could be built with today’s technology."561
H-bomb technology

Various aerospace magazines have given rough estimates of the state-of-the-art of H-bomb building technology — roughly 45 kilograms of bomb weight for each megaton of destructive power.563

A well-designed A-bomb could
be built as small as a grapefruit.

  • According to Theodore Taylor in The Curve of Binding Energy, a well-designed A-bomb could be built as small as a grapefruit.
  • Thermonuclear devices could be disguised as color television sets!
  • Cost? Ten kiloton bombs can reportedly be purchased (authorized customers only!) for $350,000.
  • Two-megaton devices can be picked up for a paltry $600,000.573 Bombs are cheap.
The neutron bomb is a clean, low-power H-bomb.
There would be no ordinary fallout.
Buildings would be left virtually unscathed,
although the passage of neutrons would make
walls, and metal slightly radioactive for a few days.

The fusion of as little as one milligram of deuterium
could produce enough neutrons to kill 100,000
humans even through one meter of solid concrete.
Neutron bomb

The aliens may be cleverer than we imagine, however. They may choose to attack our nuclear power plants or our nuclear weapon depositories, and get us with our own stuff! Or they may turn to the N-bomb.

  • The neutron bomb is a clean, low-power H-bomb.
  • A-bombs use the principle of nuclear fission — a mass of U-235 or plutonium undergoes a chain reaction explosion.
  • In the H-bomb, fissile components are used to achieve the high temperatures necessary for the initiation of fusion reactions between deuterium and tritium.
  • Explosive yields are further increased by wrapping the H-bomb in a jacket of U-238, which is highly fissionable only in the presence of high neutron fluxes.

On the other hand, the neutron bomb would be a pure fusion bomb, employing no dirty fission detonator.

  • The N-bomb would release large numbers of 17 MeV neutrons over limited areas — perhaps a few kilometers in diameter.
  • These neutrons have high penetrating power, and produce secondary radiation by colliding with atomic nuclei.
  • These secondary particles are responsible for the lethality of the neutrons.
  • There would be no ordinary fallout, although the invading aliens might have to wait a short while before entering our cities.
  • Buildings and land would be left virtually unscathed, although the passage of neutrons would make walls and metal slightly radioactive for a few days.
  • The fusion of as little as one milligram of deuterium could produce enough neutrons to kill 100,000 humans even through one meter of solid concrete.
If the N-bomb was of proper size, and was
exploded at just the right height, it would spray
the area with deadly neutrons without causing
widespread firestorms and structural damage.

The N-bomb would be an excellent tactical weapon
for aliens who wanted us out of the way but wished
to examine our undamaged artifacts at their leisure.
N-bomb: more than pure fusion

 
But an N-bomb is more than just a pure fusion bomb.

  • Normal thermonuclear devices have such large blast effects that the neutron damage would be lost in the greater general destruction.
  • The range of the neutrons depends on their energy, and this is relatively constant. Hence, the trick is to build a very low yield fusion bomb, in the kiloton range.
  • If the N-bomb was of proper size, and was exploded at just the right height, it would spray the area with deadly neutrons without causing widespread firestorms and structural damage.
  • The N-bomb would be an excellent tactical weapon for aliens who wanted us out of the way but wished to examine our undamaged artifacts at their leisure.
Figures released by the Atomic Energy Commission in the
early 1960s show that a one gigaton warhead detonated
about 16 kilometers up could be expected to start fires
over an area of more than 700,000 square kilometers.
Gigaton yield devices

Of course, H-bombs can always be made as large as desired. Gigaton yield devices (1000 megatons) have been seriously discussed, and are usually referred to as "doomsday bombs."

  • Robert Salkeld suggests that a gigaton bomb burst in our upper atmosphere would ignite all combustible substances (forests, buildings, humans) in a 600 kilometer circle below.561
  • Figures released by the Atomic Energy Commission in the early 1960s show that a one gigaton warhead detonated about 16 kilometers up could be expected to start fires over an area of more than 700,000 square kilometers.525
Salted dirty bombs

 
Others have estimated that 20-gigaton devices could be "salted" to make them dirtier.

  • A bomb wrapped in sodium would release intense, quick-killing radioactive fallout with a half-life of only fifteen hours (24Na).
  • If the wrapping were cobalt instead, the fallout (60Co, half-life 5.3 years) would kill very slowly, but would last a long time.
  • Or both could be incorporated in a single weapon. As one writer dryly pointed out: "The sodium-24 would knock out those who didn‘t get into deep shelters, and the cobalt-60 would immobilize those who did."525
But the true doomsday bomb is the one which,
if used, could destroy all human life on Earth.

Physicist W.H. Clark, a nuclear weapons
technologist, has estimated that at least
1000 gigatons of nuclear explosives would
be required to wipe out the human race.

Freeman J. Dyson, at Princeton, comes up
with more conservative figures:
3000 gigatons to kill half the human race.
Doomsday bomb

But the true doomsday bomb is the one which, if used, could destroy all human life on Earth.

  • Physicist W.H. Clark, a nuclear weapons technologist, has estimated that at least 1000 gigatons of nuclear explosives would be required to wipe out the human race.
  • Freeman J. Dyson, at Princeton, comes up with more conservative figures: 3000 gigatons to kill half the human race.525
  • The strongest, and certainly the most obvious, argument against doomsday bombs from a military standpoint is that the attacker is destroyed along with the attacked.
  • But would this argument be persuasive for marauding off-world aliens intent on planetary destruction?
18.7 Climate Modification and High Technology Weapons
Weather warfare
goethe 341
We regard the weather as a weapon.
Anything one can use to get his way is a weapon
and the weather is as good a one as any.


The science of weather modification and climate control is still in its infancy. It is therefore much more difficult to assess the possibilities than in earlier sections. "High technology" necessarily implies a more speculative effort — not to imply that weapons discussed below are any less dangerous or less real. If any of the techniques described below turn out to be unworkable for one reason or another, it’s probably unimportant. The ETs undoubtedly have far more effective ones at their disposal!

Dr. Pierre St. Amand, doing weather modification research for the U.S. Navy in the mid-1960s, said of his work: "We regard the weather as a weapon. Anything one can use to get his way is a weapon and the weather is as good a one as any."

  • In 1974, the Pentagon conceded it had used weather warfare in Vietnam for more than seven years.
  • In point of fact, the CIA allegedly began a rainmaking project over Saigon as early as 1963.471
  • This disclosure infuriated the Soviets, who promptly introduced a resolution in the United Nations calling for multilateral renouncement of all geophysical and meteorological warfare.462
Weather modification

Man has been tampering with the weather in earnest since Schaefer and Langmuir's historic snowfall-induction experiments in 1946. Unfortunately, there have been many failures and progress has been slow.

  • Silver iodide and dry ice have been used to precipitate rain for decades, and recently another technique — liquid propane sprayed into supercooled fogs — has been added to the list.465
  • Hail suppression research appears promising,464
  • Snowfall-induction for watershed and recreational purposes has become a commercial enterprise.474
  • We can disperse fogs, prevent frost, and the NOAA's Project Stormfury has had limited success in reducing the severity of tropical hurricanes.

But man’s best efforts to date still appear rather feeble.

Earthquake generation

Could aliens find ways to generate earthquakes at will?

  • Small tremors have already been artificially created by pumping water into the ground under pressure. This lubricates the fault lines, allowing the crustal plates to slip.
  • Another technique is to set off high explosives at a weak point along a fault, jarring it loose suddenly. If the blast site were judiciously selected by alien geophysicists, the resulting quake could be devastating.
  • Finally, there is the suggestion that earthquakes might be triggered by high intensity infrasound. It is well known that microseisms occur regularly at frequencies around 0.1 Hz,628 and the possibility exists that sympathetic resonances of some kind could be set up.
  • Such oscillations could perhaps be induced using sonic booms. Researchers have discovered that infrasonic energy can be transmitted from the air to the ground; they have detected "air-coupled seismic waves resulting from fighter planes — flying at high altitudes at Mach numbers greater than 1.2. Such waves have also been detected in the ground below the paths of jet airliners."628
Hurricanes and tornadoes

The average house-rattling earthquake
liberates a total energy equivalent to
hundreds of gigatons (about 1021 joules).


Hurricanes are of similar intensity.

The average house-rattling earthquake liberates a total energy equivalent to hundreds of gigatons (about 1021 joules).

  • Hurricanes are of similar intensity.
  • But these cannot simply be "triggered" as can quakes, so we‘re faced with a much larger problem in trying to generate one.
  • Tornadoes, the smaller cousin of the tropical hurricane, may be slightly easier to manage. D. S. Halacy, Jr., in The Weather Changers, notes that "there is evidence that a strong air temperature inversion at about 2 kilometers altitude is likely to produce tornadoes."547

Assuming such conditions exist in rudimentary form, can a cyclonic disturbance be generated?

A typical tornado funnel is kept
going by a power consumption
of roughly 200,000 megawatts.
Sonic boom

Perhaps. Again, the sonic boom is our instrumentality. An aircraft flying at supersonic speeds, presenting an area of several square meters of fuselage to the onrushing atmosphere, can produce pressures equivalent to "an instantaneous 180-mph hurricane" over a swath a few hundred meters wide beneath it.524

  • It’s possible that a rapidly circling fleet of supersonic flying machines could induce cyclonic motion in the already unstable air.
  • Bernard Vonnegut, a General Electric weather modification scientist, notes that a typical tornado funnel is kept going by a power consumption of roughly 200,000 megawatts.547

Could such a tornado be dispersed? That is, have we a defense if the ETs shoot tornadoes at our cities?

Weather bomb

A decade or two ago, it was suggested that a "weather bomb" could be exploded in or near a twister, literally blowing it out. This idea has been used in science fiction stories,683 but, as Halacy says: "Recent studies of the power involved in a typical tornado indicate that an H-bomb would be needed."547 Perhaps the cure is worse than the illness!

Tsunamis / Meteoroids / Planetoid Oceanic Impact

■ Seismic sea waves have been sighted as high
   as 30 meters on many occasions.

■ There are reports of a 50 meter wave following
   the great Krakatoa volcanic eruption in 1883.

■ The Guinness Book of World Records lists a record
   wave at 67 meters which supposedly appeared
   off the coast of Valdez, southwest Alaska in 1964.

■ But there are reports in reputable journals
   of still higher crests.

Tsunamis

What about generating huge tsunamis, popularly known as "tidal waves"? Tsunamis are generally caused by seaquakes on the ocean floor, and some of the techniques described for earthquake generation might be applicable here.

  • Seismic sea waves have been sighted as high as 30 meters on many occasions.
  • There are reports of a 50 meter wave following the great Krakatoa volcanic eruption in 1883.
  • The Guinness Book of World Records lists a record wave at 67 meters which supposedly appeared off the coast of Valdez, southwest Alaska in 1964,360
  • But there are reports in reputable journals of still higher crests.684

Other techniques for generating tidal waves have been suggested, such as the detonation of a one-gigaton thermonuclear device submerged a few kilometers under the ocean surface. This would produce a wave nearly 30 meters high.

Meteoroids

But the most ingenious idea is the planetoid attack.
Meteoroids pass close to Earth all the time.

  • For instance, on 30 October 1937, Hermes (a small planetoid about one kilometer in diameter) passed within 800,000 kilometers — about twice the distance to the Moon.563
  • The Apollo planetoids pass as close as a few million kilometers on a regular basis. These objects range from a few kilometers to as large as thirty kilometers in diameter.
  • It is estimated that the Earth has been struck by one of these larger meteoroids about once every few hundred million years.598
  • If the aliens were able to latch onto one such chunk of rock and iron, a few well-placed H-bombs could alter its trajectory very slightly — just enough to nudge it into a collision course with Earth.

Table 18.5 Seismic Wave Heights for Planetoid Oceanic Impact*

(mean impact velocity 10 km/sec)

table 18 5 seismic wave heights for planetoid oceanic impact 400
Planetoid Oceanic Impact

If a planetoid one kilometer in radius were to strike our planet:

  • It would gouge out a trench 80 kilometers in length and at least eight kilometers deep.
  • More than four times as deep as the Grand Canyon.414

But the surface of our planet is mostly water, so a sea landing is more likely.
What if the object were to strike an ocean? (Table 18.5)

  • Oceanographers have calculated that such an impact in, say, the central part of the Atlantic Ocean, would initially form a transient rim crater — a monstrous wall of water — on the order of three to six kilometers high.596
Planetary flooding

A multiplication of the terrestrial water
supply by a factor of four would be
required for complete inundation
of all the continents.
Planetary flooding

What about planetary flooding? Astronomer Stephen H. Dole has estimated that a multiplication of the terrestrial water supply by a factor of four would be required for complete inundation of all the continents.214 Where might aliens find this much water?

Not on Earth, certainly! One old idea is the atmospheric precipitator, a device capable of precipitating out all the water held in the humid. atmosphere. However, simple calculations reveal that if all the liquid in our skies were suddenly condensed, we‘d be standing ankle deep in water. It’s possible that highly localized flooding could occur, but a widespread terrestrial deluge is quite impossible using this technique.

The two icecaps contain a total of 23 million
cubic kilometers of ice.

■ With all this water, the absolute sea level
    will rise only about fifty meters, leaving
    most of Earth’s surface high and dry.

■ Unfortunately, many of the world’s most
    populous cities are located near the coast.
Melting polar icecaps

 
Perhaps ETs could melt the polar icecaps.

  • The two icecaps contain a total of 23 million cubic kilometers of ice.367
  • With all this water, the absolute sea level will rise only about fifty meters, leaving most of Earth’s surface high and dry.
  • Unfortunately, many of the world’s most populous cities are located near the coast. Dr. Howard A. Wilcox in Hothouse Earth has shown that 33 of the 50 largest metropolitan areas on Earth would probably be inundated.
  • This would displace about 71% of the population of those 50 cities alone — some 200 million humans.688
Lampblack dusting of polar icecaps

Wilcox suggests that icecap melting may occur naturally if mankind continues to increase its worldwide energy consumption exponentially. But we are concerned here with the possibility of aliens purposefully thawing the poles. Halacy relates that the Russians have experimented with increasing the melting rate of snow.547 This is accomplished by dusting the surface with lampblack, causing the ice to absorb solar heat more rapidly and melt. Halacy estimates that to spread a film of carbon black one-tenth of a millimeter thick over the entire northern polar region would require nearly two billion tons of the stuff. A fleet of 1000 B-52H bombers would require 50,000 missions to complete the dispersal. This technique clearly leaves much to be desired.

Could nuclear devices be used to melt the icecaps? The energy equivalent required for this feat is roughly one billion megatons. If the ETs have this kind of firepower available, why should they bother melting ice with it?

■ If the Sun’s rays were suddenly cut off, the
   atmosphere would cool to freezing, the approximate
   temperature of the ocean, in a matter of days.

■ From then on, the temperatures would drop much
   more slowly, since the huge volume of the ocean
   would act as a giant thermal buffer.

■ However, it is believed that the Ice Ages were brought
   about by temperature changes as small as 10 °C.

Precipitate an ice age

As Robert Frost agonized over the decision of whether to die by fire or ice, let us now consider a weapon that could cause an ice age to occur on Earth.

  • It has been suggested that clouds of particles be circulated in an interior solar orbit, or giant sheets of reflective foil interposed between Sun and Earth, thus causing our planet to cool rapidly.
  • If the Sun’s rays were suddenly cut off, the atmosphere would cool to freezing, the approximate temperature of the ocean, in a matter of days.
  • From then on, the temperatures would drop much more slowly, since the huge volume of the ocean would act as a giant thermal buffer.
  • However, it is believed that the Ice Ages were brought about by temperature changes as small as 10 °C.
  • We could be in big trouble in very short order.

Neither of the above proposals is workable, however. Thermal agitation and the solar wind would rapidly disperse the orbital gas cloud (or the foil), and a few warhead-tipped missiles strategically detonated would probably be enough to wreck the entire scheme.

Disperse fine dust

Disperse fine dust


Using particles of diameters of 0.01-0.1 microns,
an effective job could probably be done with
about 20 million metric tons of the stuff.


If the aliens build a linear induction catapult
on the lunar surface.

■ Each shipment from the hypothetical ET Moon
    colony contains about ten cubic meters of fine dust.
■ It would take about one year to blot out our
    sunlight if they send off one parcel every minute!


There are two great advantages to this weapon
— from the aliens‘ point of view.

■ First, the cooling is probably irreversible
   and would precipitate an Ice Age on Earth.
■ Second, there is virtually no defense against
   its use, as it would be impossible to scoop out
   dust dispersed randomly throughout our
   atmosphere as fast as the ETs could dump it in.


About the only alternative to surrender would
be a direct frontal assault on the Moon colony.

The best way to artificially cool a planet is to disperse fine dust throughout its atmosphere, way up in the stratosphere above the rain clouds. This elevates the planetary albedo, causing solar radiation to be reflected back into space. The planet will begin to cool.

Lunar induction catapult

Using particles with diameters of 0.01-0.1 microns, an effective job could probably be done with about 20 million metric tons of the stuff. If the aliens build a linear induction catapult on the lunar surface, and each shipment from the hypothetical ET Moon colony contains about ten cubic meters of fine dust, it would take about one year to blot out our sunlight if they send off one parcel every minute!

There are two great advantages to this weapon — from the aliens‘ point of view.

  • First, the cooling is probably irreversible and would precipitate an Ice Age on Earth.
  • Second, there is virtually no defense against its use, as it would be impossible to scoop out dust dispersed randomly throughout our atmosphere as fast as the ETs could dump it in.685
  • About the only alternative to surrender would be a direct frontal assault on the Moon colony.
Ultraviolet radiation exposure

There are other devious tricks the aliens could attempt with our aerosphere. As noted earlier, exposure to ultraviolet radiation can cause skin cancer, severe burns, and "snow blindness."

  • The Sun puts out lots of UV, but these rays never reach the Earth’s surface.
  • This is because the natural protective ozone layer generated by the atmospheric oxygen screens them out.
  • Ozone is present everywhere in our air, but most of it is concentrated in the stratosphere at an altitude of about 20-30 kilometers.
  • If we could collect all the ozone from a column of air stretching from the ground to the borders of space, we‘d find that each square meter has only about four grams of this precious allotrope of oxygen above it.
  • Were we to completely destroy this protective chemical layer, about 64 watts per square meter of harmful ultraviolet radiation would pelt us from the sky.
Ozone reduction

Bromine is so effective at destroying ozone
that "it could be used militarily."

■ Approximately four kilograms of bromine
   dispersed in the stratosphere over each
   square kilometer of the Earth’s surface
   will result in virtually total deozonification.

■ To deozonify the entire world would require
   about two million metric tons of liquid bromine.
■ Aliens can purchase liquid bromine for 30¢/gallon
   — provided they buy in 2300 gallon tank car lots.
■ This works out to about $52 million
   - not counting cost of delivery to the stratosphere
   - for eliminating our planet’s ozone screen.

Anyone exposed to UV more than a minute
■ Would receive severe second degree burns
■ Blinded in seconds should he look skyward
■ Terrestrial flora would begin to perish within hours.

Aliens may decide to try to relieve our atmosphere of its ozone. Nitrogen oxides, SST emissions, fluorocarbons and other industrial aerosols are already beginning to do a fine job of this, but the ETs undoubtedly will want to hurry matters along. How might they go about the construction of a deozonification weapon?

  • Dr. Michael B. McElroy, professor of Atmospheric Sciences at the Center for Earth and Planetary Physics at Harvard University, has intimated that bromine is so effective at destroying ozone that "it could be used militarily."414
  • Any halogen will do, but apparently the brownish-orange liquid element, acting as a catalyst to decompose the ozone back into oxygen, does it best.
  • Each halogenic atom injected into the stratosphere can theoretically catalyze as many as a thousand reactions before it becomes chemically locked in a relatively inert form.520
  • A simple calculation demonstrates that approximately four kilograms of bromine, dispersed in the stratosphere over each square kilometer of the Earth’s surface, will result in virtually total deozonification.
  • To deozonify the entire world would require about two million metric tons of liquid bromine.*
  • The supply officer at Dow Chemical Corporation in Walnut Creek, California tells me that the aliens can purchase liquid bromine from him for 30¢ a gallon — provided they buy in 2300 gallon tank car lots.
  • This works out to about $52 million — not counting the cost of delivery to the stratosphere — for eliminating our planet’s ozone screen.
  • Studies show that anyone exposed to the downpour of ultraviolet radiation for more than a minute would receive severe second degree burns, and would be blinded in seconds should he cast his eyes skyward.417
  • Terrestrial flora would begin to perish within hours.445
Other highly speculative "high technology" weapons

We may someday find ourselves attacked
by a giant "doomsday machine."

Such a possibility was explored in a Star Trek
adventure of the same name.

A giant robot "planet-killer" was roaming the
galaxy, chopping whole planets into rubble with
antiparticle beams and stoking its nuclear fires
with light elements extracted from the debris.

Our only defenses would be ingenuity and luck.

There are several other highly speculative "high technology" weapons. These weapons are wholly infeasible using existing human technology — but of course this doesn‘t restrict the aliens, who are all the more delighted at our lack of efficacious defenses.

Runaway chain reaction

Dr. Horace Dudley suggests that it may be possible to induce a runaway chain reaction in our atmosphere. He says that if a large enough nuclear device were detonated in open air, a worldwide conflagration might result.457 Although many would scoff at this idea, apparently Compton himself once performed a calculation to estimate the likelihood of such an event. The result? A small, but non-zero, probability.

Doomsday machine

We may someday find ourselves attacked by a giant "doomsday machine." Such a possibility was explored in a Star Trek adventure of the same name. A giant robot "planet-killer" was roaming the galaxy, chopping whole planets into rubble with antiparticle beams and stoking its nuclear fires with light elements extracted from the debris. Our only defenses would be ingenuity and luck.

Black holes

Black holes, if you believe they exist, could even be used against us. Quantum black holes may exist, holes with relatively small masses and unimaginable densities. Theoretical physicists such as Dr. Stephen W. Hawking of Cal Tech (currently Cambridge University) have calculated that quantum holes with masses greater than about a billion tons will not have evaporated yet. If such a hole was to become trapped by a planet, it would slowly "digest" the body, eventually

If asteroids are shot into a star,
  ■ Their sudden vaporization may cause
     severe instabilities
  ■ Leading to an explosion of the sun itself.

The "classic" technique is
  ■ Shklovskii’s ten billion megawatt graser.
Supposedly, it could induce
  ■ A powerful Type II supernova
  ■ In any metal rich star greater than about
     five solar masses.

Using this scheme, Sol could not be detonated.
However, there are at least
  ■ 200 supernovable stars within
  ■ 100 light years of Earth

100 light years equals the distance of:
  ■ Minimum biological effect for supernovae.

resulting in a slightly larger quantum hole — and no planet.686

Solar detonation

But if not the planet, then perhaps its sun. Niven and Pournelle have suggested, in the fictional The Mote in God’s Eye, that if asteroids are shot into a star, their sudden vaporization may cause severe instabilities leading to an explosion of the sun itself.668 But the "classic" technique, which is discussed at greater length in the following chapter, is Shklovskii’s ten billion megawatt graser.3 Supposedly, it could induce a powerful Type II supernova in any metal rich star greater than about five solar masses. Hence, using this scheme, Sol could not be detonated. However, there are at least 200 supernovable stars within 100 light years of Earth, the distance of minimum biological effect for supernovae.468, 469, 498 As technologist Adrian Berry remarks of this weapon: "Blowing up the sun … would be a perfect Götterdammerung for a besieged warlord. It would be a spectacle to surpass all others; but the fact that nobody would survive to witness the effects might, paradoxically, make the action even more attractive to warped or highly 'poetic' minds."77

Galacticide

Still worse, the aliens could commit galacticide. Near the Galactic Core, stars are much more densely packed than out here near the rim. In more than one science fiction tale, a supernova occurring in the Core initiates a chain reaction of stellar explosions, spreading outward in a spherical wave at the speed of light. The entire Galaxy is doomed!687, 607


* Between 1961 and 1971, the U.S. military dropped nearly 50,000 metric tons of herbicides on the forests of Vietnam. This represents about 2% of the mass of bromine the ETs would have to use to deozonify the Earth.

18.8 The Ultimate Weapon

Friendship: the Ultimate Weapon

■ Opposition may be wiped out by inducing friendship.

■ Friendship cannot harm friends or be turned against
    the original wielder.

■ It is inexpensive and doesn‘t depend on surprise.

■ And, in the long run, resistance to it is impossible.

It seems to me that in that least developed of all fields
of human understanding, the human mind itself,
must lie the Ultimate Weapon. But there’s one comfort;
whoever develops it will be our friend.

In 1952, the late John W. Campbell, Jr., wrote an editorial in Astounding Science Fiction entitled "The Ultimate Weapon."193 The discussion below draws heavily from his work, as his analysis has retained its luster even after twenty-five long years of human progress on this planet.

What, it might be asked, would be the characteristics of the Ultimate Weapon
— an irresistible force for which no defense exists?

  1. It must absolutely wipe out all opposition.
  2. It should be of such nature that no resistance to it is possible.
  3. It must be such that the opposition cannot turn it against the original wielder.
  4. It must annihilate all opposition, yet must not harm friends.
  5. It should not damage any useful or constructive forces.
  6. It should be of a catalytic nature, self-propagating, such that, once loosed, even the destruction of the original source cannot defeat it.
  7. It will render all present weapons inoperative.
  8. Its power should be such that no power in the Universe can stand against it.
  9. Its effect should not depend on surprise, so that even pre-erected defenses cannot defeat it.
  10. It should cost very little to use.
  11. The field where it has once been used should be permanently uninhabitable by the opposition, but freely accessible to friends.

What weapon imaginable could accomplish so much, so perfectly? As Campbell notes, the Ultimate Weapon must wipe out all opposition, but this does not necessarily imply that men must die. And since any physical weapon can be countered by physical forces, the Ultimate Weapon must be nonphysical. The wielder must desire to wipe out opposition, not fellow sentients.

Opposition may be wiped out by inducing friendship. Friendship cannot harm friends or be turned against the original wielder. It is inexpensive and doesn‘t depend on surprise. And, in the long run, resistance to it is impossible.

Campbell concludes: "It seems to me that in that least developed of all fields of human understanding, the human mind itself, must lie the Ultimate Weapon. But there’s one comfort; whoever develops it will be our friend."

  Chapter 19 ♦ Planetary Engineering and Galactic High Technology   
19.0 Planetary Engineering and Galactic High Technology
arthur clarke 360


Big and Costly are
no match for Want.

Living on the surface of a single planet almost inevitably forces us to think small. We tend to view with awe the mighty works of human technology — the Panama Canal, the Empire State Building, the Aswan Dam, the Saturn V rockets. But alien engineers may command vastly greater energies and forces than human scientists can dream of today. We are the backwoodsmen of the Galaxy, the poor inhabitants of a primitive Type I energy economy.

It appears to be
extremely difficult to
conceive of technologies
appropriate to Type III
galactic civilizations.

Think big

Imagining themselves to be galactic engineers, imaginative xenologists must train themselves to think big. This requires a temporary relaxation of quite normal and natural planetary chauvinisms (respecting both subject and scale). We must recognize and reject the Fallacy of the Big and Costly. Just because a project seems physically huge, even monstrously so, or incredibly expensive does not suffice to rule it out. The Great Pyramid of Cheops bears mute testimony to the obvious fact that anything physically possible can be accomplished, provided only that it is desired badly enough!

In short, we must learn to recognize that Big and Costly are no match for Want.

The purpose of this chapter is not to speculate on every conceivable extraterrestrial technology that might possibly exist, from force fields and perpetual motion machines to flushless toilets with frictionless bowls.668 Rather, the intent here is to attempt to visualize the broad limits on the technical achievements of alien civilizations of a higher order than our own. Not surprisingly, we shall discover that most of the grandiose projects that have been proposed from time to time by scientists and science fiction writers can be accomplished by ordinary Type II stellar cultures. It appears to be extremely difficult to conceive of technologies appropriate to Type III galactic civilizations.

The ultimate goal of any technology
is to enhance survival and to create
comfort, convenience, and wealth.
Comfort, convenience and wealth

The ultimate goal of any technology is to enhance survival and to create comfort, convenience, and wealth. Princeton physicist Gerard K. O‘Neill has pointed out that there are three necessary conditions for the rapid multiplication of wealth via technical advancement: Energy (see Chapter 15), materials, and land area or living space. That is, a population of wealthy and secure corporeal sentient beings must have:

  • The energy to accomplish great deeds.
  • The materials with which to build and to create magnificence.
  • The physical space in which to live out their immortal lives.
19.1 Alien Materials Technology
19.10 Alien Materials Technology

alexei panshin 345

Before considering the question of living space and artificial habitats, it is interesting to consider the kinds of materials and tools ETs may be able to use on their construction projects.

  • We may be assured that any currently available human technology will also be known to alien engineers as well, and probably in its most perfected form.
  • More intriguing perhaps are those technical skills which presently elude our grasp, yet which theory predicts are possible.
19.1.1 New Forms of Matter
Ultradense matter
larry niven 349


One teaspoon of neutronium
would weigh about
one hundred million tons.

Terran scientists concede the possible existence of ultradense matter, tiny clumps of material into which vast amounts of mass are compressed. Neutron stars formed by the partial gravitational collapse of massive suns are believed to consist of at least 80% pure "neutronium." Such an astronomical object is essentially a gigantic atomic nucleus, reaching a density of 1017 kg/m3 inside a typical 20-kilometer-wide star. Put into proper perspective, a single teaspoon of neutronium would weigh about one hundred million tons — roughly the equivalent of 30,000 Saturn V moon rockets.

Ultra-thin sheets of superdense
matter would be more than a
trillion times stiffer than the
hardest steel known to man.

A sheet only 1 mm thick would
have the strength of a 1000-
kilometer-thick block of steel.
Neutronium

While there are many technical difficulties to be surmounted, it is conceivable that matter of this density could be used as a building material. Ultra-thin sheets of superdense matter would be more than a trillion times stiffer than the hardest steel known to man. Projectiles could not pierce of dent it until they too were made of the same material. Neutronium shields would be impervious to almost all forms of radiation even at extreme intensities. A sheet only 1 mm (10-6 meter) thick would have the strength of a 1000-kilometer-thick block of steel.

Neutronium plates could also be used to design a local antigravity field.2740 While the gravity around a spherical mass (e.g. planets) is radial, the field across a disk is uniform except for edge effects. Newton's law for disks is g = 4Grt, where r is density, t is thickness, and G is the universal gravitation constant.

We can imagine placing a 0.4 mm-thick neutronium disk above ground, care fully supported by a structure with four stilts. The gravity beneath the sheet would be zero, the upward 1-gee pull of the neutronium exactly canceling the 1-gee downward pull of the Earth. A similar trick could be employed to enable astronauts to withstand higher accelerations in their starships. A vessel accelerating at a steady one gee could be designed with a 0.4 mm-thick neutronium disk embedded in the forward bulkhead. The crew would feel weightless when under weigh at one gee.

Elementary particle gases

Another useful advanced alien technology is the production of elementary particle gases. In order to make a gas, the particles must be long-lived and electrically neutral.2821 Only two particles satisfy both of these criteria: neutrons and neutrinos. There is much recent evidence that it may be possible to design a magnetic bottle to hold condensed cold neutrons,2822 although preliminary calculations indicate that the maximum attainable gas density would be no more than about 10-6 gm/cm3.2740 A neutronium box lined with beta emitter perhaps could be used to contain and store a neutrino gas.2014

If ETs manage to assemble and store dense
neutron and neutrino gases, they will have
practical alchemy at their disposal.

They will be able to transmute virtually any
chemical element into any other by immersing
the object to be transmuted into the gas.

If ETs manage to assemble and store dense neutron and neutrino gases, they will have practical alchemy at their disposal. They will be able to transmute virtually any chemical element into any other simply by immersing the object to be transmuted into the gas. Depending on the object and the gas, any one of the following four nuclear reactions may occur:

zMa + no —>zMa+1 zMa + anti-no —> zMa-1
zMn —> z+1Ma zMa + anti-n —> z-1Ma

where M is any atom, z is atomic number (protons in nucleus), a is atomic weight (neutrons and protons in nucleus), no is neutron, n is neutrino, and anti-no and anti-n the respective antiparticles. The reactions above also produce a variety of additional particles and so are incomplete as shown, but the basic idea remains.

Superheavy elements

Lead into gold

To turn lead into gold, the ancient alchemists' dream, we treat 82Pb208 in a condensed cold antineutron gas until it transmutes to 82Pb197, after which it is immersed in a trapped antineutrino gas to convert it into 79Au197 — the naturally-occurring isotope of gold.

More interesting and useful, however, is the creation of new superheavy elements that do not occur in nature. Transuranic elements from neptunium-237 up to element-106 have already been manufactured from lighter nuclei in giant cyclotrons and particle accelerators at great expense of time and effort. And only microscopic quantities are available. Neutron and neutrino gases would make things a lot easier.

It should be possible in principle
to design a hand pistol whose
“bullets“ are really
miniature atomic bombs.
Miniature atomic bombs

For instance, a piece of plutonium placed in a magnetic bottle containing condensed cold neutrons would sponge them up quickly and transmute into an extremely high atomic weight isotope — perhaps a denser and more stable form of matter. Subsequent immersion in neutrino gas could convert this superheavy plutonium into a different element altogether. Elements 118 and 168 — which have not yet been produced in human laboratories — should be heavy inert gases like argon and xenon. Element 126 is predicted to have properties similar to normal plutonium, and might permit much smaller nuclear reactors because of the greater atomic density.2850 There are also military applications. Only small amounts of these superheavy radionuclides would represent an explosive "critical mass," so it should be possible in principle to design a hand pistol whose “bullets“ are really miniature atomic bombs.

Trapped neutrinos would have many other fascinating uses. These particles interact little with ordinary matter, so neutronium-collimated beams could be used for point-to-point straight-line communication directly through solid masses such as planets. Objects made of ultradense matter could be “x-rayed“ by neutrino beams focused by neutronium lenses.

Quark thread

Material objects as we know them are held
together by electromagnetic forces.

The nuclei of atoms are held together by
the “strong force,“ which is about 100 times
more powerful than the electromagnetic.

Material objects as we know them are held together by electromagnetic forces. But the nuclei of atoms are held together by the “strong force,“ which is about 100 times more powerful than the electromagnetic. It may be possible to produce neutronium wire utilizing the strong force, spools of which would be many orders of magnitude stronger than any material known to present human science. Another possibility is subnuclear rope or quark thread. Nuclear physicists today believe that all elementary particles are themselves built up from combinations of “quarks“ stuck together by “gluons.“ A macroscopic chain of these subnuclear building blocks, fastened by gluons, should be incredibly strong and thin.

Magnetic monopoles

According to theory, monopoles should weigh
more than 200 times the mass of a proton.

  ■ A physicist has predicted that two monopoles
     together would generate a force 18,000 times
     greater than the normal electromagnetic
     interaction between two protons.
  ■ The science of quantum magnetodynamics,
     if it ever comes into existence, will deal with
     the strongest nuclear interaction imaginable.

Many years ago the famous Italian physicists P.A.M. Dirac hypothesized the existence of magnetic charges analogous to the electron, which he called magnetic monopoles.2823 According to theory, monopoles should weigh more than 200 times the mass of a proton. Physicist Paul B. Price at the University of California at Berkeley has predicted that two monopoles together would generate a force 18,000 times greater than the normal electromagnetic interaction between two protons.2824 The science of quantum magnetodynamics, if it ever comes into existence, will deal with the strongest nuclear interaction imaginable.

Metamatter

Given the high binding energies available in monopole-monopole interactions, there may exist a whole new class of elements we‘ve never seen before.1224 Monopolium, or monopole metamatter, may have a wide range of weird and exotic properties. It will almost certainly be denser and stronger than neutronium. Monopolic hydrogen might consist of a “north“ magnetic monopole orbiting a “south“ monopole, forming heavy, stable aggregates of macroscopic matter. Meta matter filaments may be hundreds of times stronger than nucleon chain.*


* Experimental searches for magnetic monopoles haven't found any yet. See Carrigan,1506 Ross,1499 and the summary of early work compiled by Karlssen.1513

19.1.2 Energy Storage and Mining Techniques
john milton 315


Chunk of metal size of a pen
— less than half a kilogram.


Its continuous energy output:
4 megawatts of power.

Imagine a chunk of dense grey metal, roughly the size of a fountain pen and weighing less than half a kilogram. Its continuous energy output is nearly 4 megawatts of power, falling off to 2 megawatts after two months have elapsed. Even after a year it is putting out as much heat as a large domestic furnace.

Californium-254

This substance actually exists!81 It is the radioisotope Californium-254, an element known to human science but which has never been produced in macroscopic quantities. If aliens have done so, the possibilities for exploitation of such a compact energy source are staggering — high performance light-weight electric vehicles, portable kilowatt-power radio broadcasting stations, hand-held megajoule laser rifles … the list is virtually endless.

Subcritical nuclear reactors
■ Normally, atomic fission piles must be
   made of a certain minimum [critical] size.
■ This is because the neutrons which initiate
   fission reactions arise randomly from
   within the fissionable material itself.
■ There is some evidence that nonstatistical
   means for controlling neutrons may exist.
■ Thus controlled, neutron emission would
   no longer be random and vastly improved
   efficiencies should be possible.
Subcritical nuclear reactors

Robert Forward has suggested that it might be possible to build "subcritical nuclear reactors."2014 Normally, atomic fission piles must be made of a certain minimum size. This is because the neutrons which initiate fission reactions arise randomly from within the fissionable material itself. But there is some evidence that nonstatistical means for controlling neutrons may exist.2822 Thus controlled, neutron emission would no longer be random and vastly improved efficiencies should be possible. Tiny, portable fission reactors could probably be built to service aircraft and surface vehicles. Reactors using nonradioactive lightweight metals such as beryllium or lithium would also be possible.

Planetary rotation

There are a number of other unusual energy sources. Although we don‘t ordinarily think of it as such, planetary rotation is an excellent storehouse of energy. The spinning Earth, if slowed to a dead stop, would free about 2.6 × 1029 joules — enough to power human civilization at its current rate of consumption for a billion years into the future. Sol, if similarly halted, would liberate 1.2 × 1036 joules.

Although we don‘t ordinarily think of it as
such, planetary rotation is an excellent
storehouse of energy.

■ Earth, if slowed to a dead stop, would free
   about 2.6 × 1029 joules - enough to power
   human civilization for a billion years.
■ Sol, would liberate 1.2 × 1036 joules.

An even better place to store huge
quantities of energy is in rotating chunks
of ultradense matter.

■ Hawking black holes would be ideal for
   the purpose
Hawking black holes

An even better place to store huge quantities of energy is in rotating chunks of ultradense matter. Hawking black holes would be ideal for the purpose. A 1016 kg HBH would be heavy enough not to evaporate very energetically (only about 16 kilowatts spontaneous), light enough to utilize in a space-based power storage station (mass equivalent to a 16-km-wide asteroid), and stable enough to serve as power center for a long-lived civilization (lifetime about 1012 eons). Its radius would be subatomic, about 10-11 meters, and energy could be stored and retrieved by imparting rotation via electromagnetic field coupling. Spun up to a maximum operating tangential velocity of 10%c, synchrotron radiative losses from the system would be extremely low. The spinning HBH could store up to 2 × 1030 joules of energy — enough to power present-day humanity for 9 billion years.

Mining worms

A wide variety of new mining techniques can also be imagined. In one of his science fiction novels, Larry Niven speculates on the possibility of specially bioneering organism which he calls “mining worms“:

A mining worm is five inches long and ¼-inch in diameter, mutated from an earthworm. Its grinding orifice is rimmed with little diamond teeth. It ingests metal ores for pleasure, but for food it has to be supplied with blocks of synthetic stuff which is different for each breed of worm — and there's a breed for every metal. … What breaks down the ores is a bacterium in the worm's stomach. Then the worm drops metal grains around its food block, and we sweep them up.231

Hyperaccumulators

This idea is not at all farfetched. Various plants and animals are known to be "hyperaccumulators" of specific minerals or metals. For instance, the so-called “copper flower“ native to Zaire has a dry weight that is 1.3% copper.2852 The subject of artificial mining organisms has already been discussed in Chapter 16.

Subterrenes

Arthur C. Clarke proposes that subterranean automated probes — “subterrenes,“ as he calls them — be designed to explore and exploit at least the entire crustal region of any terrestrial planet. Burrowing through solid rock using powerful rf radiation, ultrasonics, or laser heating, subterrenes could circumnavigate whole worlds down to depths of hundreds of kilometers, searching for deposits of rare minerals and lodes of precious metals.2841 Says Clarke:

The main problem with materials mined from planets
is that they lie at the bottom of a deep gravity well.

As we have already seen, space is the proper
environment for stellar and galactic civilizations.

So it is far more economical for such cultures
to mine material that is already aloft.

All the scientific observations and collection of samples could be done automatically according to a prearranged program. With no crew to sustain, the vehicle could take its time. It might spend weeks or months wandering around the roots of the Himalayas or under the bed of the Atlantic before it headed for home with its cargo of knowledge.55

Deep gravity well

The main problem with materials mined from planets is that they lie at the bottom of a deep gravity well. As we have already seen, space is the proper environment for stellar and galactic civilizations. So it is far more economical for such cultures to mine material that is already aloft.

Asteroid mining

Asteroid mining is within the abilities even of human Type I technology. The late Dandridge M. Cole and Donald W. Cox once calculated that to move a 3 billion ton iron meteoroid from the asteroid belt to a parking orbit around Earth would require about 8.4 × 1018 joules of energy.563 (Recent analyses put this figure slightly higher.2843) This is the same as two hundred 100-megaton H-bombs assuming a 25% propulsive efficiency.

According to Cole and Cox, a small atomic bomb would be set off near the asteroid's surface to form a crater. Subsequent blasts could then be fired in this crude thrust chamber. Another proposal offered by Gerard O‘Neill is to use a “mass driver“ to propel the flying mountain of metal.2710 Using electromagnetic forces, small pieces of the asteroid would be flung from the driver as reaction mass, propelling the giant mother lode to Earth. A prototype mass driver has already been constructed and was successfully tested at the Massachusetts Institute of Technology in 1977.

19.2 Extraterrestrial Habitat Engineering
19.20 Extraterrestrial Habitat Engineering

Table 19.1 Power, Energy, and Mass Available to Extraterrestrial

Civilizations in Various Stages of Their Development

table 19 1 power energy and mass available to et civilizations 400
Power, Energy and Mass Available to ET Civilizations

Ultimately the key
to all technological
accomplishment is
energy.

Most of the discussion thus far has centered on the technical advances that could be achieved by Type I civilizations. Domiciled on a planet, living space will not be a major problem for such cultures. But emergent Type II societies will find no such ready-made living quarters in orbit. A species that wishes to expand its energy base and move into space must learn how to design and construct its own artificial habitats with a closed ecology and a controlled environment.

Yet ultimately the key to all technological accomplishment is energy. We have discussed this at great length in an earlier chapter, but it is now necessary to make explicit the critical difference between energy and power.

Simply stated, energy defines what a
civilization can do whereas power defines
how fast the civilization can do it.

The distinction is important because the
maximum technical achievement of any
race is energy-limited, not power-limited.
Difference between energy and power

Simply stated, energy defines what a civilization can do whereas power defines how fast the civilization can do it. The distinction is important because the maximum technical achievement of any race is energy-limited, not power-limited.

In Chapter 15, in the interests of straightforward exposition, we made the tacit assumption that the rate of hydrogen fusion burning in stars was the maximum rate at which energy could be delivered to a technical culture from its sun. This assumption may not be valid for many advanced extraterrestrial societies.

Table 19.2 Summary of Proposed Planetary,

Stellar, and Galactic Engineering Projects

   Terraforming
table 19 2a 460
   Moving and Mining
table 19 2b 460
   Space Habitats
table 19 2c 460
Proposed Planetary, Stellar, and Galactic Engineering Projects

By tampering with the normal
processes within its sun a technical
civilization can increase the total
amount of energy that is available.

By tampering with its sun, a Type II
civilization should be able to boost its
useful power output to 6 × 1031 watts
— an increase of nearly six orders of
magnitude over the nominal value.

Table 19.1 gives the total energy available to each class of civilization. The alert reader will have noticed that the energy figures on the one hand, and the power and lifetime figures on the other hand, cannot be reconciled. The reason for the discrepancy is this: Some alien cultures may choose to use up their total energy reserves in a manner which is far more efficient than a stellar furnace normally permits. In other words, by tampering with the normal processes within its sun a technical civilization can increase the total amount of energy that is available to it. Over its normal lifespan the typical star will convert its hydrogen to energy with a net lifetime efficiency of perhaps 0.06% — a far cry from the 1% efficiency that may be had if the aliens turn off their sun and use their own fusion plants to burn the fuel.

Increased burn rate
The situation is rather like a suicide mission.
Since shortened life has been accepted, one is
free to devote more resources to the present.
There is much less future to save for.

While this may be viewed as irresponsible by
some, it may also be argued that it is better
to experience a brief but glorious career than
a drawn-out bland existence.

Furthermore, ETs may elect to burn their hydrogen legacy at a faster rate than natural processes would normally allow. This will inevitably result in a shorter lifetime for the civilization, but this penalty is offset by the grander technological feats which may be accomplished with the vastly greater power expenditure (Table 19.2). To take a simple example: By accepting a lifetime of only one million years, and by tampering with its sun, a Type II civilization should be able to boost its useful power output to 6 × 1031 watts — an increase of nearly six orders of magnitude over the nominal value.

The situation is rather like a suicide mission. Since shortened life has been accepted, one is free to devote more resources to the present. There is much less future to save for. While this may be viewed as irresponsible by some, it may also be argued that it is better to experience a brief but glorious career than a drawn-out bland existence.

In the final analysis, an intelligent race that chooses to expand into space is ultimately limited only by the amounts of energy and raw mass that are available to it.

19.2.1 Terraforming
freeman dyson 310


From the point of view
of a Type II culture
terraforming techniques
should represent a fairly
primitive technology.

If living space is in short supply on the home planet, one logical alternative is to move some of the population and growth activities to other worlds. The typical habitable solar system will have from 7-13 planets and as many moons, but it is highly unlikely that more than one of these has a natural environment tolerable to interplanetary pioneers. As with Sol's family of worlds, most will be too hot or too cold or too dry or too wet to permit immediate habitation.

Saturn's rings — If water proves to be too
scarce or too difficult to exploit, scientists are ready
with the most grandiose scheme proposed to date.

Saturn's rings are believed to consist primarily of
flying chunks of water-ice. These icy boulders
could be gathered together and welded into “a string
of huge, frozen pearls, each the rival of Phobos.“

Outfitted with propulsion and automated guidance
systems, the caravan of giant icebergs majestically
peel away from Saturn in a long, steep dive sunward.
Engineering on a grand scale

Terraforming is a form of planetary engineering on a grand scale. Just as buildings and cities are designed to suit human comfort, it is entirely feasible to consider the modification of planetary environments to suit human (or alien) needs.1977 Worlds which are unearthlike can be made more earthlike and may then be colonized and exploited by man.

There have been many proposals and suggestions as to how to go about terraforming the planets and moons of our own solar system. Only a few of these will be considered briefly here, because it turns out that in all cases the energy and mass requirements are well within the operating budgets of Type I planetary civilizations. In other words, from the point of view of a Type II culture terraforming techniques should represent a fairly primitive technology.

The Big Rain

Perhaps inspired by Poul Anderson's short story entitled “The Big Rain,“ published in 1955, Dr. Carl Sagan in 1961 proposed a terraforming project to modify the environment of Venus.1481 Our sister planet has a hellish climate, with temperatures upwards of 750 °C and pressures of 90 atm at the surface. To prepare it for human habitation it will be necessary to lower the surface temperature and pressure, and to elevate by at least two orders of magnitude the fraction of molecular oxygen present in the atmosphere. Most of the air is carbon dioxide, and this must be eliminated as well.

Venus
Our sister planet has a hellish climate,
with temperatures upwards of 750 °C
and pressures of 90 atm at the surface.
Terraforming Venus

Sagan suggests the injection of blue-green algae into the Venusian atmosphere at high altitudes where it is relatively cool. These tiny organisms would consume the CO2 by growing more algae cells with water and aerial nutrients. Molecular oxygen would be expired as a waste product. Over a period of several years the carbon dioxide level begins to drop, thus reducing the green-house effect and cooling the planet overall.2633 When the ground was sufficiently cool, cargo landers armed with fusion bombs could be de-orbited and set down on the surface. These machines, able to burrow like moles and detonate beneath the surface, may be used to trigger new volcanic chains in order to help percolate more water into the dry atmosphere.2836 Eventually the first “big rain“ will fall. Says Sagan: "The heat-retaining clouds will partly clear away, leaving an oxygen-rich atmosphere and a temperature cool enough to sustain hardy plants and animals from Earth."

How reasonable is the astronomer's proposal? In 1970 a number of biologists conducted experiments to see if earthly algae would actually grow under the extreme initial conditions found on Venus.2847, 2846 It was discovered that the most suitable strain is Cyanidium caldarium, a single-celled form that is found in hot springs on Earth. This algae produced oxygen vigorously in a hot, high-pressure atmosphere of CO2. In a typical experiment the researchers found that each million algae cells were increasing the oxygen concentration in the test tank by 380% per day.

Seeding probes

To terraform the atmosphere of Venus is not a very difficult undertaking from the standpoint of energy and mass requirements. If we dispatch an armada of 500 seeding probes to our neighbor world, each armed with a thousand in-dependently-targetable payload capsules containing 1 ton of Cyanidium caldarium per capsule, this would result in the dispersal of a kilogram of living blue-green algae cells over each square kilometer of the planet's surface. The total mission mass is about 109 kg, and the total energy required is about 1018 joules — both well within the budgetary limitations of a Type I civilization.

The present lunar air has a total mass of about
10 tons. This arises mainly from outgassing from
the interior, without which the entire atmosphere
would quickly be swept away by the solar wind.

If the atmosphere of the Moon was increased
to a mass of at least 100,000 tons it would be
driven into a “long-lived state“ which would
drastically reduce losses to the solar wind.

To produce a breathable “shirtsleeve“
atmosphere, about 1018 kilograms of O2
must be pumped into the lunar environment.
This should require a total energy expenditure
of about 1024 joules.
Terraforming Luna

Small, airless terrestrial worlds such as Luna are also suitable for terraforming projects. Richard R. Vondrak of the Department of Space Physics and Astronomy at Rice University recently suggested a method for creating a comfortable artificial lunar atmosphere.656  The present lunar air has a total mass of about 10 tons. This arises mainly from outgassing from the interior, without which the entire atmosphere would quickly be swept away by the solar wind.

Vondrak calculates that if the atmosphere of the Moon was increased to a mass of at least 100,000 tons it would be driven into a “long-lived state“ which would drastically reduce losses to the solar wind. According to him:

If one wanted intentionally to create an artificial lunar atmosphere, gases can be obtained by heating or vaporization of the lunar soil. Approximately 25 megawatts are needed to produce 1 kg/sec of oxygen by soil vaporization. [Another] efficient mechanism for gas generation is subsurface mining with nuclear explosives. A 1-kiloton nuclear device will form a cavern approximately 40 meters in diameter from which 107 kg of oxygen can be recovered.656

To produce a breathable “shirtsleeve“ atmosphere, about 1018 kilograms of O2 must be pumped into the lunar environment. This should require a total energy expenditure of about 1024 joules. Again, both mass and energy figures lie within the budget of an ambitious mature Type I civilization.

Martian terraforming
Researchers once speculated that the proper
positioning of large masses in orbit around
the planet [Mars] would alter its equinoctal
precession period. This would cause
a perpetual “Spring“ season planetwide.

A wide variety of Martian terraforming techniques have been proposed from time to time. Joseph A. Burns and Martin Harwit of the Center for Radiophysics and Space Research at Cornell University once speculated that the proper positioning of large masses in orbit around the planet would alter its equinoctal precession period.1282 This would cause a perpetual “Spring“ season planetwide, similar to that predicted by Sagan's "Long Winter" model of the Martian climate.1267

Pushing Phobos

One scheme involves pushing Phobos from its present equatorial orbit to a new one inclined 45° to the Martian equator. The total energy required to execute this maneuver would be about 1023 joules. Unfortunately, Burns and Harwit admit, the orbit of Phobos would begin to precess and might foil the entire scheme. Their second proposal involves capturing roughly 25% of the matter in the nearby asteroid belt and using that mass instead of Phobos to swing Mars around. While this might work, at least two orders of magnitude of energy would be required.

Melt icecaps

Carl Sagan may have hit upon the cheapest way to terraform Mars.1288 He suggests that about 1010 tons of low albedo matter — such as lampblack or dark-colored vegetation — be transported to the permanent Martian polar icecaps over a period of about a century. The caps would be less reflective and would thus absorb more of the sun's energy. The ice would warm and thaw, increasing the atmospheric pressure (and the greenhouse effect) and speeding north-south convective stirring of the planetary atmosphere. A minimum of 1021 joules would be needed to accomplish this feat, and hundreds of years. There are ways to do it faster. An enormous orbiting mirror could be stationed in polar orbit to melt the icecaps by reflected or concentrated sunlight, or thermonuclear bombs could be set off to achieve similar effects perhaps in a matter of decades.1978

A more complete analysis was undertaken
by a study group at NASA-Ames in 1976.

Entitled On the Habitability of Mars: An
Approach to Planetary Eco-synthesis
,

The final report of the study attempted
to pin down the specific requirements for
successful terraforming of the Red Planet.

It was concluded that “no fundamental
limitation to the ability of Mars to support
terrestrial life has been identified.“
On the Habitability of Mars

A more complete analysis was undertaken by a study group at NASA-Ames in 1976. Entitled On the Habitability of Mars: An Approach to Planetary Eco-synthesis, the final report of the study attempted to pin down the specific requirements for successful terraforming of the Red Planet.1926 It was concluded that “no fundamental limitation to the ability of Mars to support terrestrial life has been identified.“

The scientists proposed a two-pronged attack on the problem. First, atmospheric mass should be increased by vaporizing the polar icecaps or the subsurface permafrost. If the reflectivity of the icecaps was reduced by only 5% for a period of 100 years, a kind of runaway de-ice age might be triggered “and a new high temperature climatic regime established.“ Secondly, mechanisms of genetic engineering currently available or under development could be used to construct organisms far better adapted to grow on Mars than any present terrestrial organism. In principle, the entire gene pool of the Earth might be available for the construction of an ideally adapted oxygen-producing photosynthetic Martian organism.

It was estimated that the creation of an oxygen atmosphere using known terrestrial photosynthetic lifeforms might take hundreds of thousands of years. But by altering the environment of Mars and by seeding it with appropriately bioneered organisms, the length of time to project completion could be reduced a thousandfold. Total energy expenditure for the NASA-Ames scheme: Roughly 1024-1025 joules.

Electrolysis factories

Academician N.N. Semenov, a Soviet scientist, suggests that the water locked in permafrost and polar icecaps by subjected to simple electrolysis.2849 Water molecules would be split into oxygen, which could be released into the Martian air eventually to result in a breathable atmosphere, and hydrogen, which could be collected and used for fuel in fusion power plants needed to operate the electrolysis factories. Earthlike air would result from the electrolysis of about 15% of all water believed to be present at the Martian surface, at a cost of about 1023 joules.

Caravan of giant icebergs

If water proves to be too scarce or too difficult to exploit, scientists are ready with the most grandiose scheme proposed to date. Saturn's rings are believed to consist primarily of flying chunks of water-ice. These icy boulders could be gathered together and welded into “a string of huge, frozen pearls, each the rival of Phobos.“2828 Properly outfitted with propulsion and automated guidance systems, the caravan of giant icebergs majestically peel away from Saturn in a long, steep dive sunward. What happens next has been eloquently described by Freeman Dyson:

A few years later, the night-time sky of Mars begins to glow bright with an incessant sparkle of small meteors. The infall continues day and night, only more visibly at night. Soft warm breezes blow over the land, and slowly warmth penetrates into the frozen ground. A few years later, it rains on Mars. It does not take long for the first oceans to begin to grow.2829

19.2.2 Space Habitats

Figure 19.1 Building Space Habitats

   The Lunar Base

A nuclear plant provides power for the mass-driver, which is fed with materials scooped up by vehicles such as the one in the foreground. (Painting by Pierre Mion, © National Geographic Society)2853

   Twin-engine mass-driver tug
figure 19 1b building space habitats 250

Recovery of asteroidal chunks using twin-engine mass-driver tug2710

   Island Three space community
figure 19 1c building space habitats 250

Exterior of a possible "Island Three" space community. Living areas, agriculture, and industry, though located within a few miles of each other, have separately chosen temperature, climate, day-length, and gravity. (R. Guidice, NASA)

   Model IV Colonies
figure 19 1d building space habitats 250

The largest (Model IV) Colonies, which could be functioning by 2025, will probably consist of two connected cylinders, each 19 miles long, four miles in diameter, and containing as much as 100 square miles in total land area.

The most beautiful living areas on Earth could be duplicated in the colonies. The bridge shown here, to give an idea of the dimensions involved, is similar in size to the San Francisco Bay Bridge.

A Model IV colony could hold up to several million people comfortably, but the interior design pictured here is intended for only about 200,000 inhabitants. Drawing: NASA

   The Stanford Torus Design2827 - exterior
figure 19 1e the stanford torus design 250

The Stanford torus is a proposed design for a space habitat capable of housing 10,000 to 140,000 permanent residents.

The Stanford torus was proposed during the 1975 NASA Summer Study, conducted at Stanford University, with the purpose of speculating on designs for future space colonies.

It consists of a torus, or doughnut-shaped ring, that is 1.8 km in diameter (for the proposed 10,000 person habitat described in the 1975 Summer Study) and rotates once per minute to provide between 0.9g and 1.0g of artificial gravity on the inside of the outer ring via centrifugal force.

The torus would require nearly 10 million tons of mass. Construction would use materials extracted from the Moon and sent to space using a mass driver. A mass catcher at L2 would collect the materials, transporting them to L5 where they could be processed in an industrial facility to construct the torus. Only materials that could not be obtained from the Moon would have to be imported from Earth. [from: Wikipedia]

   The Stanford Torus Design2827 - interior
figure 19 1f the stanford torus design 250

Sunlight is provided to the interior of the torus by a system of mirrors. The ring is connected to a hub via a number of "spokes", which serve as conduits for people and materials travelling to and from the hub. Since the hub is at the rotational axis of the station, it experiences the least artificial gravity and is the easiest location for spacecraft to dock. Zero-gravity industry is performed in a non-rotating module attached to the hub's axis.

The interior space of the torus itself is used as living space, and is large enough that a "natural" environment can be simulated; the torus appears similar to a long, narrow, straight glacial valley whose ends curve upward and eventually meet overhead to form a complete circle. The population density is similar to a dense suburb, with part of the ring dedicated to agriculture and part to housing. [from: Wikipedia]



By staying on planets,
the species condemns
itself to a permanent
Type I energy status.

While we may expect that Type II civilizations will certainly have the energy, mass, and technological sophistication to terraform virtually any terrestrial world in their system, the pressures of population expansion are not long alleviated by inhabiting other planets. Living area is increased by an order of magnitude at best, a bounty gobbled up in only 300 years assuming population expands at the modest rate of 1% per annum. And by staying on planets, the species condemns itself to a permanent Type I energy status.

Cities in space

The remedy to this dilemma is to build giant habitats in free space, far from the baleful encumbrances of planetary surfaces. In recent times Gerard K. O‘Neill and others have advocated the construction of enormous artificial habitats in Earth orbit (see especially Heppenheimer,2826 Johnson and Holbrow,2627 and O‘Neill2710) using materials lofted from the lunar surface by electromagnetic mass driver.2844 Preliminary estimates from several sources indicate that it is technically feasible to construct cities in space able to house 10,000 people and having a total mass of about 1010 kg. The main cost in energy comes from pitching the construction materials off the lunar surface. This cost amounts to about 1017 joules altogether. This is low enough to be feasible even for Type I civilizations such as our own — provided we do not build too many of them. A Type II culture, of course, is rich enough to build all of them it wants.

Island Two community

After a sufficient number of habitats have been erected in space — which O‘Neill calls Island One communities, the process of expansion would become self-sustaining.

An Island Three community would measure
more than 6 km in diameter and 32 km in length,
with a total land area of 1300 square kilometers
and a human population of several million persons.

Structures up to four times larger are possible
within the limits of current human technology.

These Island Four communities would have land
areas more than half the size of Switzerland, and
populations numbering in the tens of millions

A group of Island One communities could pool their resources to form an economic cooperative, and engage in the construction of an even larger Island Two community. This monstrous edifice might be a giant, slowly-spinning cylinder perhaps 2 km in diameter and 6 km in length, housing a total of 140,000 people. The interior could be designed with a number of small villages separated by parkland or forest areas, each similar in size and population density to a small Italian hill town.2710

Island Three and Four community

Still larger habitats could be built, since there is no gravity in free space to give engineers headaches. An Island Three community would measure more than 6 km in diameter and 32 km in length, with a total land area of 1300 square kilometers and a human population of several million persons. And, according to O‘Neill, structures up to four times larger are possible within the limits of current human technology. These Island Four communities would have land areas more than half the size of Switzerland, and populations numbering in the tens of millions (Figure 19.1).

Hollow planetoid cities, similar in size and mass
to the largest of the O‘Neill communities, could
be constructed in a fairly straightforward manner.

Once the hollow world has solidified and cooled
off, a giant mirror is affixed to direct solar power
down the central axis to bring sunshine to
the interior.

Water, soil, and biology are now moved in.
More than 780 km2 are available for habitation.
Hollow planetoid cities

Many scientists believe that it is wasteful to construct space cities out of lunar materials. It is cheaper, they claim, to use raw materials that are not trapped at the bottom of a gravity well. So, we mine the asteroids.2864 Dandridge Cole and Donald Cox showed in 1964 that hollow planetoid cities, similar in size and mass to the largest of the O‘Neill communities, could be constructed in a fairly straightforward manner.563

The first order of business is the erection of a giant solar mirror several kilometers in diameter.2848 Formed under conditions of zero gravity, it could have a very lightweight construction. Perhaps an old Echo balloon could be inflated, sprayed with a thin layer of something to harden it, then cut in half and silvered on the inside.

Next, an elongated asteroid should be selected, perhaps measuring a kilometer in diameter and two kilometers in length with a mass of about 1013 kg. The mirror is then used to bore out a hole down the central axis of the object. This is done by focusing the sun's rays on the mountain of nickel-iron and vaporizing away some of the metal. After it has cooled, the longitudinal hole is charged with large tankards of liquid water. The ends are securely plugged and welded shut using heat from the large mirror.

The planetoid is set spinning slowly around its long axis. The entire metal body is bathed in concentrated solar heat directed at its surface by the mirror. Gradually the temperature rises, finally reaching the melting point all over the surface. Slowly the heat creeps inward until virtually the entire object is molten or soft.

The central axis is the last place to melt if the procedures have been correctly executed. So long as this region remains solid, the melting body retains a cylindrical shape rather than coalescing into a formless spheroid. Just before the central region melts, the axial water tanks explode into super-heated steam. The immense pressure blows the asteroid into a giant nickel-iron balloon some 10 km in diameter and 20 km in length.

Sunshine to the interior

Once the hollow world has solidified and cooled off, construction crews affix the giant mirror to one end and direct solar power down the central axis to bring sunshine to the interior. Water, soil, and biology are now moved in. More than 780 km2 are available for habitation.

Life would be interesting inside a large O‘Neill community or Cole planetoid. The horizon, and landscape, rises overhead in the distance. Since only 3 km of air are required to appreciably scatter sunlight, the sky will be blue. If the planetoid is given a slight equatorial bulge and the endcaps are shaded from the sun, perpetual rain and snow will fall at the poles. The ice melt flows down rivers carved into the inside walls into a wraparound central circular lake that rises skyward in a beautiful blue arc at either horizon. Artificial spin-gravity may be set as low as desired, so it is possible to don a pair of wings and take to the air like birds.2429

19.2.3 Planet Moving and Star Mining
Energy Requirements for Planetary, Stellar, and Galactic Transport Operations

Table 19.3 Energy Requirements for Planetary,

Stellar, and Galactic Transport Operations

table 19 3 energy requirements for transport operations 360

They will have
magnificent dreams.


Their technology
will not lag far
behind their ambition

We are still thinking small, unfortunately.* We have not yet mentioned a single engineering project that could not be successfully mounted by a Type I planetary culture, at least in theory. A Type II society living in the space surrounding its sun will be a proud, vigorous, expansive large-scale civilization. They will have magnificent dreams, and their technology will not lag far behind their ambition.

A stellar culture will have access to the entire mass and derivable energy from all the matter in its own solar system. From Table 19.1 we have already seen that this represents considerable potential for energetic economic development of interplanetary space. Theoretically, a stellar society has at least 1030 kilograms and more than 1043 joules to play around with.

How grand may be their monuments to civilization? As even terrestrial engineers are well aware, any construction project has two basic requirements: (1) Delivery of materials to the construction site, and (2) proper deployment of those materials once they have arrived. So what can Type II cultures do?

While the technology needed to move planets and stars around is absolutely huge when measured against the normal human scale, the energy requirements for such operations turn out to be well within reach of Type II civilizations.

While the technology needed to move planets and
stars around is absolutely huge when measured
against the normal human scale, the energy
requirements for such operations turn out
to be well within reach of Type II civilizations.


Asteroid and planet-moving are no real problem.
The interstellar transport of stars will give Type II
societies some trouble, and it may take a Type III
organization to perform the maneuver gracefully.

The complete fusion combustion of all the
deuterium in Earth's oceans would be insufficient
to impart solar escape velocity to the planet.


If the hotter-burning hydrogen fusion reactions
are used, however, Earth's seas could be drained
and used as fuel to propel our world to the stars.

Table 19.3 above shows the energies necessary to move several different kinds of bodies. Values are given both for solar escape velocity (~104 meter/sec) and for the minimum reasonable interstellar transport velocity (1%c).

Clearly, asteroid and planet-moving are no real problem. The interstellar transport of stars will give Type II societies some trouble, and it may take a Type III organization to perform the maneuver gracefully.

Darol Froman, Technical Associate Director of the Los Alamos Scientific Laboratory in New Mexico, has pointed out that the complete fusion combustion of all the deuterium in Earth's oceans would be insufficient to impart solar escape velocity to the planet.2831 If the hotter-burning hydrogen fusion reactions are used, however, Earth's seas could be drained and used as fuel to propel our world to the stars.

Froman suggests that roughly a quarter of the fuel be used to escape from Sol, another quarter to enter the target stellar system many light-years away, and the remaining half for heat, lighting, and propulsion en route. The planetary fusion thrusters should be located at the South Pole, so that Earth's natural rotation can be used for guidance and directional stabilization. Science fiction writer Stanley Schmidt has done a creditable job in describing the local effects of terramotive operations.2832


* A sobering example of this appears in Isaac Asimov's Foundation Trilogy.2944 Trantor, the Imperial capitol of all the Galaxy, is described as a giant ecumenopolis, a “planetary city“ of gleaming metal covering 190 million km2 (about the surface area of Mars) and extending nearly 2 km deep.

  • There are 40 billion human bureaucratic inhabitants.
  • This seems a rather impressive piece of architecture, especially since each person would have a generous 107 m3 all to himself which is at least two orders of magnitude more room than most people have on Earth today.
  • But the mass and energy requirements are far less impressive. If made of steel the total mass of the city of Trantor would come to about 1019 kg. Only a million average-sized asteroids need be captured for this purpose, and only about 1026 joules would be required to transfer them to the site of construction — say, Eart orbit. (This is the major energy cost of the project.)
  • So mighty Trantor, pride of the Galactic Imperium and capitol world of the entire Milky Way, could be constructed with some difficulty by a mature Type I civilization or with ease by a Type II civilization.
Delivery and Deployment

Fusion Pogo Rocket

How might gas giants be pushed around the solar system? We know Type II societies have the energy, but what kind of technology might be involved? In one of his science fiction tales of the distant future, Larry Niven describes how it might be possible to use what he calls a Fusion Pogo Rocket. A tremendous fusion motor hooked up to a reworked military laser cannon might turn the trick on our Uranus:

It's a double-walled tube, very strong under expansion shock. It floats vertical in the upper air. Vents at the bottom let in the air, which is hydrogen and methane and ammonia, hydrogen compounds, like the air that the sun burns. You fire laser cannon up along the axis, using a color hydrogen won‘t let through. You get a fusion explosion along the axis, and the explosion goes out and up. The whole mass blasts out the top, through the flared end. It has to have an exhaust velocity way higher than Uranus's escape velocity. The motor goes smashing down into deeper air. You see there's a kind of flared skirt at the bottom. The deep air builds up there at terrific pressure, stops the tube and blasts it back up. You fire it again... The atmosphere is fuel and shock absorber both — and the planet is mostly atmosphere.2636

Stars, too, may be moved about, using a tuned
Shklovskii Mining Graser at reduced power.

This powerful gamma-ray laser could be aimed
to strike a glancing blow at the target star on the
side opposite the direction you want it to move.

The sun will spew out star-stuff and begin to move off
in the direction dictated by Newton's laws of motion.
Interstellar transport of stars

Stars, too, may be moved about, using a tuned Shklovskii Mining Graser (see next page) at reduced power. This powerful gamma-ray laser could be aimed to strike a glancing blow at the target star on the side opposite the direction you want it to move. The sun will spew out star-stuff and begin to move off in the direction dictated by Newton's laws of motion. Scientists agree that this technique may work, because the same basic principle of propulsion has been observed to occur naturally with comets. These “dirty snowballs,“ swinging close to our Sol, are heated on the sunward side. Material boils off asymnietrically and jets out into space, deflecting the orbit by a kind of rocket effect.*

So delivery of the materials to the construction site is no problem for stellar cultures. What about deployment? Once a planet or star has been moved to where it is needed, how do we get the mass out?

One of the most popular techniques for taking
planets apart is called centrifugal disruption.

This requires the accelerated rotation of a planet up
to the point at which it fractures under internal stresses.

When the rotation rate of a planet the size of Earth has
been brought up to about 100 minutes per revolution,
the equator is just ready to take off into space.

The process of disassembling the planet will proceed
steadily as its angular momentum is increased.
Centrifugal disruption

One of the most popular techniques for taking planets apart is called centrifugal disruption. This requires the accelerated rotation of a planet up to the point at which it fractures under internal stresses. Slowly the world unravels, sloughing off outer layers like a successive molting. If the speed-up is continued long enough, the entire body will be disrupted into asteroid-sized chunks of mass.

Freeman Dyson has suggested that centrifugal disruption could be accomplished by laying a net of conductive windings around a planet along the lines of latitude, each strand carrying a current on the order of microamperes per square centimeter.1450 These cables would give rise to a magnetic field. Orbiting electrical generators (which produce an opposing magnetic field) then trace out paths which produce a net torque on the body, causing it to spin faster. A continuous stream of generators must pass through the correct maneuvers to maintain the electromagnetic accelerative force, each unit converting its orbital momentum into planetary spin momentum. An alternative disruption technique is available to civilizations that have mastered fusion power — simple tangential reaction thrust generated by sideways-firing equatorial fusion rockets would also spin up a world to destruction.2833

When the rotation rate of a planet the size of Earth has been brought up to about 100 minutes per revolution, says Dyson, "the equator is just ready to take off into space. From this point on, the process of disassembling the planet will proceed steadily as its angular momentum is increased." The total energy required to spin Earth up to the transition point is about 4 x 1030 joules; for Jupiter, about 9 × 1034 joules will be necessary. (After 97% of Jupiter's mass has been stripped away, we are left with a large terrestrial world that was once the core of the jovian — a mass of from 5-10 Earth-masses. We may decide to cannibalize it for heavy metals, or it may be saved for reasons of aesthetics, nostalgia, or terraforming and habitation operations.)

Gas giants disassembled bit by bit
Suborbital fusion satellites and nuclear ram-scoops
■ could dip down into the jovian atmosphere,
■ scoop up some hydrogen,
■ fuse it into heavier elements,
■ use the resulting energy to propel the transmuted
   matter into a parking orbit near the construction site.

J.H. Fremlin and Anthony Michaelis have suggested that gas giants could be disassembled bit by bit.2955 Suborbital fusion satellites and nuclear ram-scoops could dip down into the jovian atmosphere, scoop up some hydrogen, fuse it into heavier elements, and use the resulting energy to propel the transmuted matter into a parking orbit near the construction site. The energy needed to move Jupiter's entire mass into an Earth parking orbit along a minimum energy transfer trajectory is about 1036 joules.

Explosive disruption

Still a third possibility is Explosive Disruption. Theoretically, with enough energy under harness any planetary body can quite literally be blasted into rubble. While we don‘t know what kind of explosive device might be used (perhaps a 6-km-wide antimatter asteroid?), it is a simple matter to calculate how much energy would be required. The total energy to disrupt a world expIosively is on the order of its gravitational potential energy. This works out to about 2 × 1032 joules for Earth and 2 × 1036 joules for Jupiter. Again, no problem at all for Type II cultures.


Galaxy-moving

* Galaxy-moving should be possible for Type III civilizations using a related technique. Synchronized application of the Graser to a few percent of the stars in a galaxy would cause billions of suns to move off in the preferred direction. The rest of the galaxy, bound to the moving stars by gravity, would slowly follow.

The Shklovskii Mining Graser

Figure 19.2 The Shklovskii Mining Graser

   Shklovskii Mining Graser

ABOVE: the Shklovskii Mining Graser strikes a glancing blow to an alien sun, causing it to move off in the opposite direction due to the rocket effect.

   The Crab Nebula

ABOVE: the graser beam is cranked up to maximum power and directed straight at the star. The remnants of the resulting supernovae might appear as the Crab Nebula does in this photograph.

The Mining Graser will
probably be “self-critical“
— that is, an enormous
nuclear reactor that emits
most of its laser energy
directly as coherent light.

In a related manner, stars too may be disassembled. The energy required to blow a sun to bits by brute force explosive disruption is about 2 × 1041 joules, which would be quite a challenge for an enterprising stellar society. But this is not very elegant. The renowned Soviet astrophysicist Iosef S. Shklovskii has considered the possibility that an artificial supernova might be induced in a single star.20 Shklovskii believes that a Type II civilization should have no difficulty constructing a gigantic gamma-ray laser (or “graser“) operating at a wavelength of 1 Angstrom and at power levels of at least 1015 watts. This Mining Graser (Figure 19.2) would have a forward aperture diameter of about 10 meters and could focus on a 10-km-wide spot at a star's surface from a safe distance of 10 light-years. (Unmanned automated devices can venture closer.) The Mining Graser will probably be “self-critical“ — that is, an enormous nuclear reactor that emits most of its laser energy directly as coherent light.284)

Spontaneous supernova

According to an astrophysical theory proposed by British astronomer Geoffrey Burbidge, a concentrated gamma-ray flux should cause exceedingly high temperatures to arise in the outer layers of a star. If this temperature was hot enough, a spontaneous supernova might result. It is estimated that a flux of 107 watts/m2 may be sufficient to initiate a supernova explosion.2837

When this occurred, perhaps 0.1% of the star's mass would be converted directly into energy — about 1043 joules. In addition to the release of copious amounts of x-rays and other radiative energy that could be collected and stored, a significant fraction of the stellar mass will be propelled outward at speeds up to 1000 km/sec.

The beam strikes a glancing blow first on one side,
then the other.

Star-stuff spews equally from either side,
so the sun goes nowhere.

Sweepships collect and store the unburned stellar
hydrogen as it streams from the photo-sphere.

Slowly the star is whittled down to size as the
bulk of its mass is siphoned off and taken away.

This rich expanding gas cloud may be harvested by diligent interstellar mining engineers, using squadrons of robot drones equipped with giant electromagnetic ramscoops. Heavy elements generated by the explosion would be swept up, refined and milled by a flotilla of gargantuan factory sweepships in a "cage" of circular orbits surrounding the demolished star.

Turn stars off

The Shklovskii Mining Graser can also be used to turn stars off. The beam strikes a glancing blow first on one side, then the other, and so forth. Star-stuff spews equally from either side, so the sun goes nowhere. Sweepships collect and store the unburned stellar hydrogen as it streams from the photo-sphere. Slowly the star is whittled down to size as the bulk of its mass is siphoned off and taken away. Finally, down to less than 1% of its original weight, the once-mighty celestial furnace flickers out. The hot jovian planet that remains may now be disassembled by the more conventional means discussed earlier.

19.2.4 Large Scale Biospheric Engineering
The Dyson Sphere
edward young 325


The Sphere is massive
about 15 solar masses.

Assuming a Type II civilization can find all the materials and energy it may require, normal expansive development and material growth may proceed. As it matures, the stellar culture may place more and more artifacts in solar orbit in an attempt to soak up every last joule of the sun's output. They may not want to go to the trouble of turning their star off, or they may lack the technological acumen to do it, or they may find the idea unethical, unnatural, and morally repugnant.

Dyson Sphere
"a ping pong ball with a star in the middle"

■ If the entire planetary mass of Sol's system was
   spread into a solid shell at the radius of Earth's orbit,

■ the resulting artifact would run a bit less than
   10 meters thick.

■ The interior surface area would be the equivalent
   of a billion Earths,

■ about three hundred million billion square kilometers
   of habitable land.

So while it is not inevitable, the chances are good that at least some extraterrestrial Type II cultures wish to preserve their sun in its natural state. On the basis of this assumption, Freeman Dyson predicted more than twenty years ago that the end result of interplanetary industrialization may be a shell of artifacts completely encasing the star. Seen from a great distance this "Dyson Sphere" would radiate only waste heat at a wavelength of about 10 µm in the deep infrared.1022

Theoretically, a normal solar system should have plenty of mass with which to construct a solid Dyson Sphere around a star. (At least one writer has likened this to "a ping pong ball with a star in the middle."673) If the entire planetary mass of Sol's system was spread into a solid shell at the radius of Earth's orbit, the resulting artifact would run a bit less than 10 meters thick. The interior surface area would be the equivalent of a billion Earths, about three hundred million billion square kilometers of habitable land.

Mechanical difficulties of the Dyson Sphere

There are a number of mechanical difficulties associated with the solid Dyson Sphere. If rotating, the equatorial section would bow outward due to centrifugal force. Similarly, the "poles" would lack support and flatten, causing dynamic instability and collapse of the structure. If stationary, solar tidal forces would give rise to large compressive stresses.* The shell seems too thin to maintain proper rigidity. Furthermore, the gravity on the outer surface would be only 0.6 milligees so no reasonable atmosphere could be held. Objects or gases or people living on the inside would fall gently into the sun. There have been many attempts to save the Sphere by positing antigravity devices at critical points along the surface, but these heroic efforts remain unconvincing. For a Type II society, at least, a solid Dyson sphere is out of the question.

The Square-Cube Law predicts that we'll get more
square meters of living area out of each kilogram
of building materials used if we construct the smallest
habitable structures possible.

Dyson himself proposed that the Sphere should be
comprised of swarms of relatively small space habitats.

Anyway, the Square-Cube Law predicts that we'll get more square meters of living area out of each kilogram of building materials used if we construct the smallest habitable structures possible. For this reason, Dyson himself proposed that the Sphere should be comprised of swarms of relatively small space habitats. If we use Cole Planetoids equipped with large, very thin solar collector mirrors, we could build about 1014 of them interior to Earth's orbit. Each would weigh about 1013 kg, and could be pressurized with a breathable oxygen atmosphere. If they were constructed with a doubling time of 25 years, only 1200 years would be required to complete the transition to a mature Type II stellar industrial civilization.


* This may not be fatal to the project. According to equations for gravitational tidal stress on large structures provided by Dyson,1450 the minimum materials strength needed to hold a solid Dyson Sphere together should be no more than 1012 N/m2. Flawless diamond has a theoretical maximum compression strength of ~1012 N/m2 and shearing strength ~1011 N/m2 so it may be possible to work something out.2838 At compressions above 1011 N/m2, the normally colorless diamond takes on a delicate light brown color.2939

The Niven Ringworld

Figure 19.3 The Niven Ringworld753

   Figure 19.3 The Niven Ringworld753
figure 19 3 the niven ringworld 400
   Artist's conception of The Niven Ringworld
   Artist's conception of The Niven Ringworld

Ringworld


a great ribbon of matter
shaped like a hoop


with the same diameter
as Earth's orbit

Larry Niven has come up with a fascinating alternative to the Dyson Sphere. His proposal: A giant Ringworld (Figure 19.3), a great ribbon of matter shaped like a hoop with the same diameter as Earth's orbit.753 The great structure whirls around the sun at 1240 km/sec to provide a constant 1-gee gravity across the Ring. If the entire planetary mass of our solar system was used, the Ringworld would measure about 1000 meters thick. At last — a project truly worthy of a stellar culture.

Walls 2000 kilometers high at either edge of the Ringworld ribbon, aiming toward the central star, would be enough to hold in most of the atmosphere. An inner ring of shadow squares — orbiting panels to block out parts of the sunlight — provide a day/night cycle for Ringworld inhabitants. By bobbing the structure up and down, the apparent angle of the sun changes and we get seasons. You could even see the stars, as well as a beautiful checkered arc, traversing the nighttime sky.

The interior surface area would be equivalent to three million Earths, and the artifact would require on the order of 1036 joules to assemble — a project well within reach of a Type II civilization. The engineering effort would necessarily be a massive one. Looking at the outer surface of the Ringworld, Niven says:

 The Niven Ringworld 

Click for Synopsis   

The Niven Ringworld


  • The great structure whirls around the sun at 1240 km/sec to provide a constant 1-gee gravity across the Ring
  • If the entire planetary mass of our solar system was used, the Ringworld would measure about 1000 meters thick
  • Walls 2000 kilometers high at either edge of the Ringworld ribbon, aiming toward the central star, would be enough
    to hold in most of the atmosphere

An inner ring of shadow squares

  • Orbiting panels to block out parts of the sunlight
  • Provide a day/night cycle for Ringworld inhabitants
  • By bobbing the structure up and down, the apparent angle of the sun changes and we get seasons
  • You could even see the stars, as well as a beautiful checkered arc, traversing the nighttime sky

  • The interior surface area would be equivalent to three million Earths
  • The artifact would require on the order of 1036 joules to assemble

Looking at the outer surface of the Ringworld:

  • Seas would show as bulges, mountains as dents
  • Riverbeds and river deltas would be sculptured in
  • There would be no room for erosion on something as thin as a Ringworld

  • Seas would be flat-bottomed — as we use only the top of a sea anyway
  • Small, with convoluted shore lines. Lots of beachfront
  • Mountains would exist only for scenery and recreation.

A large meteor would be a disaster on such a structure.

  • A hole in the floor of the Ringworld, if not plugged would eventually let all the air out
  • The pressure differential would cause storms the size of a world making repairs difficult

Seas would show as bulges, mountains as dents. Riverbeds and river deltas would be sculptured in; there would be no room for erosion on something as thin as a Ringworld. Seas would be flat-bottomed — as we use only the top of a sea anyway — and small, with convoluted shore lines. Lots of beachfront. Mountains would exist only for scenery and recreation. A large meteor would be a disaster on such a structure. A hole in the floor of the Ringworld, if not plugged, would eventually let all the air out, and the pressure differential would cause storms the size of a world, making repairs difficult.673

More than one Ringworld could circle a sun, although this would require additional mass borrowed either from the local star or from a neighboring system. Many different intelligent races could wrap noncoplanar Ringworlds around the same star, with differing radii to avoid collision and provide a variety of temperature regimes.

Topopolis
A strand of hollow metal macaroni
■ About a trillion meters long
■ Only a kilometer or two in cross-sectional diameter
■ And a few hundred meters thick

The two ends are joined together
A great hoop around the sun

■ It rotates in smoke ring fashion
   to get artificial gravity on the inner surface
■ With a complete artificial biosphere set up inside
■ And solar collectors set up outside for energy
■ This huge tunnel world would have a habitable
   surface area of only about 20 Earths

■ Each one we make costs only about 3 × 1027 joules
■ Weighs about one-thousandth as much as the Earth
Interstellar travel on Ringworld

There is also the possibility of harnessing the basic Ringworld structure for interstellar travel on a massive scale. Niven elaborates:

The Ringworld rotates at 1240 km/sec. Given appropriate conducting surfaces, this rotation could set up enormous magnetic effects. These could be used to control the burning of the sun, to cause it to fire off a jet of gas along the Ringworld axis of rotation. The sun be-comes its own rocket. The Ringworld follows, tethered by gravity. By the time we run out of sun, the Ring is moving through space at Bussard ramjet velocities. We continue to use the magnetic effect to pinch the interstellar gas into a fusion flame, which now becomes our sun and our motive power.673

Topopolis

Pat Gunkel has designed a structure analogous to the Ring but of considerably lower mass. Imagine a strand of hollow metal macaroni, about a trillion meters long but only a kilometer or two in cross-sectional diameter and a few hundred meters thick. Gunkel joins the two ends together in a great hoop around the sun, sets it rotating in smoke ring fashion to get artificial gravity on the inner surface, and calls it Topopolis.673 With a complete artificial biosphere set up inside, and solar collectors set up outside for energy, this huge tunnel world would have a habitable surface area of only about 20 Earths. But each one we make costs us only about 3 × 1027 joules and weighs only about one-thousandth as much as the Earth.

The Alderson Disk

Figure 19.4 The Alderson Disk673

   Figure 19.4 The Alderson Disk673
   Artist's conception of The Alderson Disk
   Artist's conception of The Alderson Disk

So far we've discussed projects for Type II civilizations. Let's have a look at a few designs that will require the muscle of a galactic Type III civilization.

The Alderson Disk
Useful living surface would
be the equivalent of more
than 4 billion Earths.

Dr. Daniel Alderson proposes a massive structure shaped like a giant phonograph record with the star in the center hole (Figure 19.4). Gravity will be uniform and perpendicular to the Disk everywhere except at the edges. A slow spin should partially counteract the sideways inward pull of the central star and provide a stable celestial pole. A 1000-km-high retaining wall should be constructed on the lip of the inner hole, to prevent the leakage of atmosphere into the sun.673

The Alderson Disk weighs in at about 6 × 1033 kg, or about 3000 solar masses. The innermost radius is about 50 million kilometers, just inside the orbit of Mercury; the outermost radius is set at 600 million kilometers from the sun, about midway between the asteroid belt and Jupiter. The Disk is 5000 km thick, so the surface gravity is 0.14 gees (about like Luna). If the air is pressurized to 1 atm at the surface, then the total weight of the atmosphere is only 2 × 1029 kg, less than one-tenth of a solar mass extra. Since gravity is so low, the air thins out very slowly with altitude: 40 kilometers up, the pressure is only down to 0.5 atm which is still breathable. Also, note that both sides of the artifact can be inhabited.

 The Alderson Disk 

Click for Synopsis   

The Alderson Disk

A massive structure shaped like a giant phonograph record with the star in the center hole


  • Gravity will be uniform and perpendicular to the disk everywhere except at the edges
  • A slow spin should partially counteract the sideways inward pull of the central star and provide a stable celestial pole
  • A 1000-km-high retaining wall: constructed on the lip of the inner hole to prevent leakage of atmosphere into the sun

  • The innermost radius is about 50 million kilometers, just inside the orbit of Mercury
  • The outermost radius is set at 600 million kilometers from the sun, midway between the asteroid belt and Jupiter
  • The Disk is 5000 km thick, so the surface gravity is 0.14 gees (about like Luna)

  • If the air is pressurized to 1 atm at the surface, then the total weight of the atmosphere is only 2 × 1029 kg,
    less than one-tenth of a solar mass extra
  • Since gravity is so low, the air thins out very slowly with altitude
  • 40 kilometers up, the pressure is only down to 0.5 atm which is still breathable

The Alderson Disk weighs in at about 6 × 1033 kg, or about 3000 solar masses

  • The additional land area made available is enormous
  • The useful living surface would be the equivalent of more than 4 billion Earths
  • Also, note that both sides of the artifact can be inhabited
  • Since the disk is far more massive than the central star, the sun should be bobbled up and down to create seasons
  • Computer-controlled Shklovskii Grasers mounted on the inside edge could induce vertical motion and would also serve
    to nudge the star back to center if it begins to stray towards the inside annular edge of the disk

  • Energy required to assemble the disk should be about 5 × 1044 joules — fairly trivial for a galactic culture
  • The Alderson Disk would probably be a cooperative venture of a group of Type II cultures (perhaps 10-100 of them)
  • Or of a single emergent Type III galactic civilization

Since the Disk is far more massive than the central star, the sun should be bobbled up and down to create seasons. Computer-controlled Shklovskii Grasers mounted on the inside edge could induce vertical motion, and would also serve to nudge the star back to center if it begins to stray towards the inside annular edge of the Disk. The energy required to assemble the Alderson Disk should be about 5 × 1044 joules, which should be fairly trivial for a galactic culture.

One science fiction writer waxes enthusiastic about the idea:

The Disc would be a wonderful place to stage a Gothic or a sword-and-sorcery novel. The atmosphere is right, and there are real monsters. Consider: We can occupy only a part of the Disc the right distance from the sun. We might as well share the Disc and the cost of its construction with aliens from hotter or colder climes. Mercurians and Venusians nearer the sun, Martians out toward the rim, aliens from other stars living wherever it suits them best. Over the tens of thousands of years, mutations and adaptations would migrate across the sparsely settled borders. If civilization should fall, things could get eerie and interesting.673

Due to its size, the Alderson Disk would probably have to be a cooperative venture of a group of Type II cultures (perhaps 10-100 of them) or of a single emergent Type III galactic civilization. The additional land area made available is enormous. The useful living surface would be the equivalent of more than 4 billion Earths.

Second look at the solid Dyson Sphere

The Sphere is massive
— about 15 solar masses
■ The shell is equivalent to a wall of
    solid steel more than 3 km thick
■ Much of the room is taken up by
    living quarters, passageways, etc.
■ The hull is more than 60 km deep

■ The total energy needed to assemble:
    probably run on the order of 1043 joules

■ To propel it through space at 17%c
    (the stated velocity)
    will require an additional 4 × 1046 joules

■ Surface gravity is only 1% that of Earth
■ Enough to hold a tenuous atmosphere
    just above the external armor plating
■ Part of this is interstellar gas, but
    most of it is a helium-oxygen mixture
    left over from nuclear power plants