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arXiv · 0807.1406

Markovian Approximation for the Nosé--Hoover method and H-theorem

Hiroshi Watanabe
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Abstract

A Langevin equation with state-dependent random force is considered. When the Helmholtz free energy is a nonincreasing function of time (the H-theorem), a generalized Einstein relation is obtained. A stochastic process of the Nosé--Hoover method is discussed on the basis of the Markovian approximation. It is found that the generalized Einstein relation holds for the Fokker--Planck equation associated with the stochastic Nosé--Hoover equation. The present result indicates that the Nosé--Hoover dynamics coarse-grained with time satisfies the H-theorem and therefore works as a heat bath.

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Hiroshi Watanabe. 2008-07-09. Markovian Approximation for the Nosé--Hoover method and H-theorem. https://doi.org/10.1143/jpsj.77.103001

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