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From microscopic dynamics to macroscopic irreversibility

A. Perez-Madrid
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Abstract

In this contribution we prove that the entropy of an N-body isolated system can not decrease and the entropy production should be non-negative provided the system possesses an equilibrium state. We define the entropy as a functional of the set of n-particle reduced density operators (n=0,....,N) generalizing the von Neumann fine-grained entropy formula. Additionally, as a consequence of our analysis we find the expression of the equilibrium n-particle reduced density operators which enter the definition of the entropy as well as the dissipated energy in an irreversible process.

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A. Perez-Madrid. 2006-10-02. From microscopic dynamics to macroscopic irreversibility. https://arxiv.org/abs/cond-mat/0609475

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