The irony of modern-day astrophysics is that the more astronomers study the light of the universe the darker the universe appears.
Study of the brightest galaxies in the universe persuaded astronomers that 99 percent of the matter in the universe was dark. And measurements of the brightest stars convinced astronomers that three times as much dark energy existed as did dark matter.
Because dark energy is the dominant component of the universe, the space surface of the universe, upon which all the galaxies, stars, and planets reside, expands at a progressively faster rate as the universe ages. Already, dark energy is expanding the cosmic surface at such a rapid rate that as astronomers look far away, and hence look back in time (because light takes time to travel from distant objects to the astronomer’s telescope), to observe the first stars that formed after the cosmic creation event they note that those stars, relative to us, move at just under the velocity of light. That high speed implies that in the relatively near future dark energy will accelerate the expansion of the universe at such a rapid rate that, relative to us, the first stars will travel at over the velocity of light and, thus, cease to be visible to us.
Physicists Lawrence Krauss and Robert Scherrer calculated that, because of dark energy, in the distant future observers on any planet in the universe will be fundamentally unable to ascertain any of the important features of the universe.1 In particular, it will become impossible for any physical sentient being living anywhere within the universe to determine whether or not the universe is expanding, or whether or not it has a beginning. It will also be impossible to learn anything about the origin of the elements, or to discover the existence of dark energy or the cosmic background radiation. Cosmology (the study of the origin, history, and structure of the universe) as a science inevitably must come to an end.
Dark energy implies that the later in cosmic history (later than about 14 billion years after the beginning of the universe) humans arrive, the smaller fraction of cosmic history they would theoretically be able to see. The situation is similar if humans were to arrive significantly earlier upon the cosmic scene.
It takes time for light to travel from distant galaxies to an observerâ€™s telescope. Up to the dark energy limit, the older the universe the greater the distance at which astronomers can make observations and, thus, the farther back in time they can see. The universe is now sufficiently ancient that astronomers can directly view and analyze 99.9972 percent of cosmic history and directly behold the cosmic creation event. However, the earlier in cosmic history humans arrive, the lesser the fraction of cosmic history they theoretically would be capable of observing. Thus, in the distant past cosmology as a science also inevitably must come to an end.
Both the past and the future are bad for cosmology. The present is ideal. This conclusion prompts a question: is it supernatural design or is it sheer coincidence that we humans arrive on the cosmic stage at the best possible time to witness the entire history of the universe, to study the beginning of the universe, and even to discern the attributes of the universe’s Beginner? Given that we humans also are in the best possible location to see all of cosmic history and that both this best possible time and best possible place coincide with what is best to provide us with an ideal habitat in which to live implies that it must be the former.
- Lawrence M. Krauss and Robert J. Scherrer, “The Return of a Static Universe and the End of Cosmology,” eprint arXiv0704.0221, fifth prize 2007 Gravity Research Foundation Essay Competition, to appear in General Relativity and Gravitation, October 2007.