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Can Typicality Arguments Dissolve Cosmology’s Flatness Problem?

Published online by Cambridge University Press:  01 January 2022

Abstract

Several physicists, among them Hawking, Page, Coule, and Carroll, have argued against the probabilistic intuitions underlying fine-tuning arguments in cosmology and instead propose that the canonical measure on the phase space of Friedman-Robertson-Walker space-times should be used to evaluate fine-tuning. They claim that flat space-times in this set are actually typical on this natural measure and that therefore the flatness problem is illusory. I argue that they misinterpret typicality in this phase space and, moreover, that no conclusion can be drawn at all about the flatness problem by using the canonical measure alone.

Type
Physical Sciences
Copyright
Copyright © The Philosophy of Science Association

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Footnotes

I am especially grateful to John Dougherty for helping me work through the ideas of this article and Craig Callender for suggesting investigating the general topic. Thanks also to audiences at Pittsburgh, Columbia, Bristol, and the PSA meeting, where some of this work was presented.

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