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arXiv · 1012.4622

Equilibration of quantum systems and subsystems

Anthony J. Short
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Abstract

We unify two recent results concerning equilibration in quantum theory. We first generalise a proof of Reimann [PRL 101,190403 (2008)], that the expectation value of 'realistic' quantum observables will equilibrate under very general conditions, and discuss its implications for the equilibration of quantum systems. We then use this to re-derive an independent result of Linden et. al. [PRE 79, 061103 (2009)], showing that small subsystems generically evolve to an approximately static equilibrium state. Finally, we consider subspaces in which all initial states effectively equilibrate to the same state.

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Anthony J. Short. 2010-12-21. Equilibration of quantum systems and subsystems. https://doi.org/10.1088/1367-2630%2F13%2F5%2F053009

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