Lecture 42: The Fermi Paradox
So, Where is Everybody? Interstellar colonization, in principle, is an\nexponential growth process that would fill the galaxy in a few million\nyears even with a very modest star flight capability. This is a small\nfraction of the lifetime of the Milky Way Galaxy, so the Galaxy should\nbe teaming with life. But, we so far have no compelling evidence of\nextraterrestrial visitations, alien artifacts, or any other evidences\nthat the Galaxy is populated. Physicist and Nobel Laureate Enrico\nFermi's apparent paradox and some of the proposed resolutions are the\ntopic of this lecture. I will review the Fermi Paradox and describe the\nmost common possible resolutions. The Fermi Paradox is useful in\nhelping to frame the question of extraterrestrial life, even if we so\nfar have no answers. At the end I only touch on the Rare Earth\nHypothesis, but this is a very nuanced question which requires a whole\nother lecture to explore that I have not had time to fully prepare for\nduring this busy quarter. Recorded live on 2009 Nov 30 in Room 1005\nSmith Laboratory on the Columbus campus of The Ohio State University.