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Information-Theoretical Bound of the Irreversibility in Thermal Relaxation Processes
Naoto Shiraishi1, Keiji Saito2
1Department of Physics, Gakushuin University, 1-5-1 Mejiro, Toshima-ku, 171-0031 Tokyo, Japan.
Abstract:
We establish that entropy production, which is crucial to the characterization of thermodynamic irreversibility, is obtained through a variational principle involving the Kulback-Leibler divergence. A simple application of this representation leads to an information-theoretical bound on entropy production in thermal relaxation processes; this is a stronger inequality than the conventional second law of thermodynamics. This bound is also interpreted as a constraint on the possible path of a thermal relaxation process in terms of information geometry. Our results reveal a hidden universal law inherent to general thermal relaxation processes.
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