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Why Boltzmann Brains Are Bad

Carroll, Sean M. (2017) Why Boltzmann Brains Are Bad. . (Submitted)

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Some modern cosmological models predict the appearance of Boltzmann Brains: observers who randomly fluctuate out of a thermal bath rather than naturally evolving from a low-entropy Big Bang. A theory in which most observers are of the Boltzmann Brain type is generally thought to be unacceptable, although opinions differ. I argue that such theories are indeed unacceptable: the real problem is with fluctuations into observers who are locally identical to ordinary observers, and their existence cannot be swept under the rug by a choice of probability distributions over observers. The issue is not that the existence of such observers is ruled out by data, but that the theories that predict them are cognitively unstable: they cannot simultaneously be true and justifiably believed.

Item Type:Report or Paper (Discussion Paper)
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URLURL TypeDescription paper
Carroll, Sean M.0000-0002-4226-5758
Additional Information:I have benefited from discussions with a large number of people over the years, including David Albert, Andy Albrecht, Anthony Aguirre, Charlie Bennett, Kim Boddy, Raphael Bousso, Jennifer Chen, Alan Guth, Jim Hartle, Matt Johnson, Andrei Linde, Don Page, Jason Pollack, Jess Riedel, and Mark Srednicki. This research is funded in part by the Walter Burke Institute for Theoretical Physics at Caltech, by DOE grant de-sc0011632, by the Foundational Questions Institute, and by the Gordon and Betty Moore Foundation through Grant 776 to the Caltech Moore Center for Theoretical Cosmology and Physics.
Group:Walter Burke Institute for Theoretical Physics, Moore Center for Theoretical Cosmology and Physics
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Department of Energy (DOE)DE-SC0011632
Gordon and Betty Moore Foundation776
Foundational Questions Institute (FQXI)UNSPECIFIED
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Record Number:CaltechAUTHORS:20170209-151733308
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:74201
Deposited By: Joy Painter
Deposited On:09 Feb 2017 23:41
Last Modified:03 Oct 2019 16:35

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