| That the universe itself must die was known to nineteenth-century scientists. Charles Darwin, in his Autobiography, wrote of his anguish when he realized this profound but depressing fact: "Believing as I do that man in the distant future will be a far more perfect creature than he now is, it is an intolerable thought that he and all other sentient beings are doomed to complete annihilation after such long-continued slow progress." The mathematician and philosopher Bertrand Russell wrote that the ultimate extinction of humanity is a cause of "unyielding despair." In what must be one of the most depressing passages ever written by a scientist, Russell noted: That man is the product of causes which had no prevision of the end they were achieving; that his origin, his growth, his hopes and fears, his loves and beliefs, are but the outcome of accidental collocations of atoms; that no fire, no heroism, no intensity of thought or feeling, can preserve a life beyond the grave; that all the labors or the ages, all the devotion, all the inspiration, all the noonday brightness of human genius, are destined to extinction in the vast death of the solar system; and the whole temple of Man's achievement must inevitably be buried beneath the debris of a universe in ruins—all these things, if not quite beyond dispute, are yet so nearly certain, that no philosophy which rejects them can hope to stand. Only within the scaffolding of these truths, only on the firm foundation of unyielding despair, can the soul's habitation be safely built. Russell wrote this passage in 1923, decades before the advent of space travel. The death of the solar system loomed large in his mind, a rigorous conclusion of the laws of physics. Within the confines of the limited technology of his time, this depressing conclusion seemed inescapable. Since that time, we have learned enough about stellar evolution to know that our sun will eventually become a red giant and consume the earth in nuclear fire. However, we also understand the basics of space travel. In Russell's time, the very thought of large ships capable of placing humans on the moon or the planets was universally considered to be the thinking of a madman. However, with the exponential growth of technology, the prospect of the death of the solar system is not such a fearsome event for humanity... By the time our sun turns into a red giant, humanity either will have long perished into nuclear dust or, hopefully, will have found its rightful place among the stars. Still, it is a simple matter to generalize Russell's "unyielding despair" from the death of our solar system to the death of the entire universe. In that event, it appears that no space ark can transport humanity out of harm's way. The conclusion seems irrefutable; physics predicts that all intelligent life forms, no matter how advanced, will eventually perish when the universe itself dies. According to Einstein's general theory of relativity, the universe either will continue to expand forever in a Cosmic Whimper, in which the universe reaches near absolute zero temperatures, or will contract into a fiery collapse, the Big Crunch. The universe will die either in "ice," with an open universe, or in "fire," with a closed universe. To tell which fate awaits us, cosmologists use Einstein's equations to calculate the total amount of matter-energy in the universe. Because the matter in Einstein's equation determines the amount of space-time curvature, we must know the average matter density of the universe in order to determine if there is enough matter and energy for gravitation to reverse the cosmic expansion of the original Big Bang. A critical value for the average matter density determines the ultimate fate of the universe and all intelligent life within it. If the average density of the universe is less than 10-29 gram per cubic centimeter, which amounts to 10 milligrams of matter spread over the volume of the earth, then the universe will continue to expand forever, until it becomes a uniformly cold, lifeless space. However, if the average density is larger than this value, then there is enough matter for the gravitational force of the universe to reverse the Big Bang, and suffer the fiery temperatures of the Big Crunch. | — Michio Kaku, Hyperspace: A Scientific Odyssey Through Parallel Universes, Time Warps, and the 10th Dimension, Chapter 14 – The Fate of the Universe | Indexes/12 |
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From the death of our solar system to the death of the whole universe. In such circumstances, it seems that there is no room for the Ark can be transported out of harm humane manner.
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