Sharpening the second law of thermodynamics with the quantum Bayes theorem

We prove a generalization of the classic Groenewold-Lindblad entropy inequality, combining decoherence and the quantum Bayes theorem into a simple unified picture where decoherence increases entropy while observation decreases it. This provides a rigorous quantum-mechanical version of the second law...

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Main Authors: Gharibyan, Hrant, Tegmark, Max Erik
Other Authors: Massachusetts Institute of Technology. Department of Physics
Format: Article
Language:English
Published: American Physical Society 2014
Online Access:http://hdl.handle.net/1721.1/90265
https://orcid.org/0000-0001-7670-7190
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author Gharibyan, Hrant
Tegmark, Max Erik
author2 Massachusetts Institute of Technology. Department of Physics
author_facet Massachusetts Institute of Technology. Department of Physics
Gharibyan, Hrant
Tegmark, Max Erik
author_sort Gharibyan, Hrant
collection MIT
description We prove a generalization of the classic Groenewold-Lindblad entropy inequality, combining decoherence and the quantum Bayes theorem into a simple unified picture where decoherence increases entropy while observation decreases it. This provides a rigorous quantum-mechanical version of the second law of thermodynamics, governing how the entropy of a system (the entropy of its density matrix, partial-traced over the environment and conditioned on what is known) evolves under general decoherence and observation. The powerful tool of spectral majorization enables both simple alternative proofs of the classic Lindblad and Holevo inequalities without using strong subadditivity, and also novel inequalities for decoherence and observation that hold not only for von Neumann entropy, but also for arbitrary concave entropies.
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spelling mit-1721.1/902652022-09-27T20:15:03Z Sharpening the second law of thermodynamics with the quantum Bayes theorem Gharibyan, Hrant Tegmark, Max Erik Massachusetts Institute of Technology. Department of Physics MIT Kavli Institute for Astrophysics and Space Research Gharibyan, Hrant Tegmark, Max Erik We prove a generalization of the classic Groenewold-Lindblad entropy inequality, combining decoherence and the quantum Bayes theorem into a simple unified picture where decoherence increases entropy while observation decreases it. This provides a rigorous quantum-mechanical version of the second law of thermodynamics, governing how the entropy of a system (the entropy of its density matrix, partial-traced over the environment and conditioned on what is known) evolves under general decoherence and observation. The powerful tool of spectral majorization enables both simple alternative proofs of the classic Lindblad and Holevo inequalities without using strong subadditivity, and also novel inequalities for decoherence and observation that hold not only for von Neumann entropy, but also for arbitrary concave entropies. National Science Foundation (U.S.) (Grant AST-1105835) Massachusetts Institute of Technology. Undergraduate Research Opportunities Program 2014-09-22T18:02:30Z 2014-09-22T18:02:30Z 2014-09 2014-05 2014-09-19T22:00:02Z Article http://purl.org/eprint/type/JournalArticle 1539-3755 1550-2376 http://hdl.handle.net/1721.1/90265 Gharibyan, Hrant, and Max Tegmark. "Sharpening the second law of thermodynamics with the quantum Bayes theorem." Phys. Rev. E 90, 032125 (September 2014). © 2014 American Physical Society https://orcid.org/0000-0001-7670-7190 en http://dx.doi.org/10.1103/PhysRevE.90.032125 Physical Review E Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. American Physical Society application/pdf American Physical Society American Physical Society
spellingShingle Gharibyan, Hrant
Tegmark, Max Erik
Sharpening the second law of thermodynamics with the quantum Bayes theorem
title Sharpening the second law of thermodynamics with the quantum Bayes theorem
title_full Sharpening the second law of thermodynamics with the quantum Bayes theorem
title_fullStr Sharpening the second law of thermodynamics with the quantum Bayes theorem
title_full_unstemmed Sharpening the second law of thermodynamics with the quantum Bayes theorem
title_short Sharpening the second law of thermodynamics with the quantum Bayes theorem
title_sort sharpening the second law of thermodynamics with the quantum bayes theorem
url http://hdl.handle.net/1721.1/90265
https://orcid.org/0000-0001-7670-7190
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