Search for extraterrestrial intelligence: Difference between revisions

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Revision as of 22:16, 22 July 2007

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Possible explanations for the paradox suggest, for example, that while simple life may well be abundant in the universe, intelligent life may be exceedingly rare. In [[2000]], [[Peter Ward (paleontologist)|Peter Ward]], professor of Biology and of Earth and Space Sciences at the [[University of Washington]] authored a well-received book promotingclaiming the [[Rare Earth hypothesis]]. In short, the theory claims that the emergence of complex [[multicellular life]] ([[metazoa]]) on Earth required an extremely unlikely combination of [[astrophysical]] and [[geological]] events and circumstances. This hypothesis violatescontradicts the [[principle of mediocrity]], which SETI takes as an assumption.

Another suggestion, made by astrophysicist [[Ray Norris]] in [[1999]] in [http://www.iaanet.org/publicat/acta.html Acta Astronautica] (and subsequently in [[Allen Tough]]'s book ''[http://www.ieti.org/tough/books/succeeds.htm When SETI Succeeds: The Impact of High-Information Contact]'' - ISBN 0-9677252-2-4) was that [[gamma-ray burst]] events are sufficiently frequent to sterilize vast swaths of galactic real-estate. This idea was subsequently popularized by physicist [[Arnon Dar]], and described in the [http://www.pbs.org/wgbh/nova/gamma/ PBS Nova show 'Death Star'].