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arXiv · 1806.11055

Dissipation production in a closed two-level quantum system as a test of the obversibility of the dynamics

Claudia L. Clarke·Ian J. Ford
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Abstract

Irreversible behaviour is traditionally associated with open stochastic dynamical systems, but an asymmetry in the probabilistic specification of a closed deterministic system can similarly lead to a disparity between the likelihoods of a particular forward and corresponding backward behaviour starting from a specified time. Such a comparison is a test of a property denoted obversibility, which may be quantified in terms of dissipation production as a measure of irreversibility. We here discuss the procedure needed to evaluate dissipation production in a simple, deterministic two-level quantum system described by a statistical ensemble of state vectors and then provide numerical results for illustrative situations. We consider cases that both do and do not fulfill an Evans-Searles Fluctuation Theorem for the dissipation production, and identify conditions for which the system will display time-asymmetric average behaviour as it evolves.

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Claudia L. Clarke, Ian J. Ford. 2018-08-30. Dissipation production in a closed two-level quantum system as a test of the obversibility of the dynamics. https://arxiv.org/abs/1806.11055

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