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arXiv · 1011.3508

Entropy production and equilibration in Yang-Mills quantum mechanics

Hung-Ming Tsai·Berndt Müller
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Abstract

The Husimi distribution provides for a coarse grained representation of the phase space distribution of a quantum system, which may be used to track the growth of entropy of the system. We present a general and systematic method of solving the Husimi equation of motion for an isolated quantum system, and we construct a coarse grained Hamiltonian whose expectation value is exactly conserved. As an application, we numerically solve the Husimi equation of motion for two-dimensional Yang-Mills quantum mechanics (the x-y model) and calculate the time evolution of the coarse grained entropy of a highly excited state. We show that the coarse grained entropy saturates to a value that coincides with the microcanonical entropy corresponding to the energy of the system.

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Hung-Ming Tsai, Berndt Müller. 2011-03-23. Entropy production and equilibration in Yang-Mills quantum mechanics. https://doi.org/10.1103/physreve.85.011110

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