Could There Have Been a Single Origin of Life in a Big Bang Universe?

摘要

Frank Tipler, in The Physics of Immortality, wrote about how to spread a form of traveling artificial life throughout the known, expanding universe, prior to collapse. The key is to make the Alife self-reproducing, permitting exponential growth, like life itself, but faster. We ask whether microbial extremophiles could have originated in a single location at an early phase of a big bang universe, and spread throughout the cosmos, as is commonly assumed in discussions of the panspermia hypothesis? Since the universe was much smaller when the first condensed matter appeared, this hypothesis merits consideration. In comparing particle horizons with biohorizons, we find that the answer is no: at our earliest estimated time for the origin of life, 500×10~6 years after the big bang, if life started everywhere it could, there would have had to have been at least 50,000 origins of life. In the course of our rough calculations, we introduce the concepts of the generations of life (from microorganisms to consciousness), the Biocosmological Principle that life is spread throughout the universe, life as a wave in an active medium, and the speed of life, I.e., the speed of ejecta from galaxies and lesser bodies on which life could be transported.