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Relation between the psychological and thermodynamic arrows of time

Mlodinow, Leonard and Brun, Todd A. (2014) Relation between the psychological and thermodynamic arrows of time. Physical Review E, 89 (5). Art. No. 052102. ISSN 1539-3755. doi:10.1103/PhysRevE.89.052102.

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In this paper we lay out an argument that generically the psychological arrow of time should align with the thermodynamic arrow of time where that arrow is well defined. This argument applies to any physical system that can act as a memory, in the sense of preserving a record of the state of some other system. This result follows from two principles: the robustness of the thermodynamic arrow of time to small perturbations in the state, and the principle that a memory should not have to be fine-tuned to match the state of the system being recorded. This argument applies even if the memory system itself is completely reversible and nondissipative. We make the argument with a paradigmatic system, and then formulate it more broadly for any system that can be considered a memory. We illustrate these principles for a few other example systems and compare our criteria to earlier treatments of this problem.

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Additional Information:© 2014 American Physical Society. Received 12 September 2013; published 2 May 2014. L.M. and T.A.B. would like to acknowledge fascinating and useful conversations with Sean Carroll, Murray Gell-Mann, Jonathan Halliwell, Jim Hartle, Stephen Hawking, and John Preskill. This work was supported by the hospitality of the Institute for Quantum Information at Caltech.
Group:Institute for Quantum Information and Matter
Funding AgencyGrant Number
Institute for Quantum Information and Matter (IQIM)UNSPECIFIED
Issue or Number:5
Classification Code:PACS: 05.70.Ln,, 05.90.+m
Record Number:CaltechAUTHORS:20140620-130436424
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:46399
Deposited By: Tony Diaz
Deposited On:23 Jun 2014 19:56
Last Modified:10 Nov 2021 17:25

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