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arXiv · 1909.13205

Thermodynamic entropy as a Noether invariant in a Langevin equation

Yuki Minami·Shin-ichi Sasa
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Abstract

We study the thermodynamic entropy as a Noether invariant in a stochastic process. Following the Onsager theory, we consider the Langevin equation for a thermodynamic variable in a thermally isolated system. By analyzing the Martin-Siggia-Rose-Janssen-de Dominicis action of the Langevin equation, we find that this action possesses a continuous symmetry in quasi-static processes, which leads to the thermodynamic entropy as the Noether invariant for the symmetry.

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Yuki Minami, Shin-ichi Sasa. 2019-09-29. Thermodynamic entropy as a Noether invariant in a Langevin equation. https://doi.org/10.1088/1742-5468%2Fab5b8b

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