Thermodynamic Entropy as a Noether Invariant
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Published on: July 19, 2016
Shin-Ichi Sasa1, Yuki Yokokura2,3
1Department of Physics, Kyoto University, Kyoto 606-8502, Japan.
Abstract:
We study a classical many-particle system with an external control represented by a time-dependent extensive parameter in a Lagrangian. We show that thermodynamic entropy of the system is uniquely characterized as the Noether invariant associated with a symmetry for an infinitesimal nonuniform time translation t→t+ηℏβ, where η is a small parameter, ℏ is the Planck constant, β is the inverse temperature that depends on the energy and control parameter, and trajectories in the phase space are restricted to those consistent with quasistatic processes in thermodynamics.
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