Extraterrestrial Civilizations - Isaac Asimov [126]
But what about the extraterrestrial intelligences? Assuming that they do not make use of any dream technologies we cannot even imagine at present, they too may have followed a development that makes the free-worlds a practical way (perhaps the only practical way) of sending living organisms through interstellar space.
Free-worlds may thus arise from thousands of different planetary sources, and some of them may have been moving through space, into and out of the asteroid belts of this star and that, for billions of years.
It may be that if extraterrestrial civilizations have visited us, it has been in the form of free-worlds. And if so, it may be that they have not visited Earth (in which their interest might be limited), but our asteroid belt.
It may be that when our space settlements move out into the asteroid belt we will find ourselves preempted; or perhaps find evidence that free-worlds have been there in the past and have long since gone.* Or it may be that free-worlds, on principle, avoid Sunlike stars with habitable planets. After all, for free-world purposes almost any star would do. A star might be a short-lived giant, but the free-world can stay far enough away to avoid the radiation and might not need more than, say, a century or two to build new starships out of what planetary material is available at such a distance. Even the least long lived star would last many times that period. Or (much more likely) a star might be pigmyish and cool, but the free-world would not need it for energy, just for the planetary bodies circling it.
If many civilizations adopt that technique, it may well be that some human free-world, dropping down toward some planetary system, will find it already preempted by other free-worlds that are nonhuman.
Surely by that point in history, it will be understood that it is the nature of the mind that makes individuals kin, and that the differences in shape, form, and manner are altogether trivial.
It may be that as the human free-worlds start moving outward, they will find themselves part of a vast brotherhood of intelligence; part of the complex of innumerable routes by which the Universe has evolved in order to become capable of understanding itself.
And it may be that in combination, humanity and all the extraterrestrial civilizations can advance farther and faster than any one of them could alone. If there is any chance of defeating what we now see as the laws of nature and of bending the entire Universe to the will of the intelligences it has given rise to, then it will be in combined effort that the greatest chance of success will arise.
* There is one somewhat more hopeful aspect of such a trip that I am omitting now, but that I will come back to later.
*The speed-of-light limit exists for tachyons as well as for particles with ordinary mass (tardyons) but in the case of the former, the limit is a floor rather than a ceiling. Particles with zero mass (or luxons from a Latin word for light) go just at the speed of light, or right at the limit that serves as a boundary, a “luxon wall” between our own tardyon Universe and the ultrafast tachyon Universe.
† In science fiction stories it has long been customary to get round the speed-of-light barrier by making use or some aspect of the Universe in which the barrier no longer exists. The aspect is called hyperspace or subspace, but whatever the word the imagined properties are those of the tachyonic Universe.
*For 25 years, physicists accepted the existence of the neutrino even though it had never been detected, because that existence was necessary to explain observed phenomena. Right now, physicists accept the existence of particles called quarks though they have never been detected, because that existence