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Does life's rapid appearance imply a Martian origin?

P. C. W. Davies
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Abstract

The hypothesis that the rapid appearance of life on Earth justifies the belief that life is widespread in the universe has been investigated statistically by Lineweaver and Davis. However, a rapid appearance could also be interpreted as evidence for a nonterrestrial origin. I attempt to quantify the relative probabilities for a nonindigenous versus an indigenous origin of life on Earth, on the assumption that biogenesis involved one or more highly improbable steps, using a generalization of the well known observer selection argument of Carter. The analysis is specifically applied to a Martian origin of life, with subsequent transfer to Earth within impact ejecta.

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P. C. W. Davies. 2004-03-02. Does life's rapid appearance imply a Martian origin?. https://doi.org/10.1089/153110703322736006

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