Thermodynamic entropy as a Noether invariant in a Langevin equation
arXiv:1909.13205 · doi:10.1088/1742-5468/ab5b8b
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.
12 pages, 2 figures