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Entropy production in nonequilibrium thermodynamics: a review

Giovanni Gallavotti
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Abstract

Entropy might be a not well defined concept if the system can undergo transformations involving stationary nonequilibria. It might be analogous to the heat content (once called ``caloric'') in transformations that are not isochoric (i.e. which involve mechanical work): it could be just a quantity that can be transferred or created, like heat in equilibrium. The text first reviews the philosophy behind a recently proposed definition of entropy production in nonequilibrium stationary systems. A detailed technical attempt at defining the entropy of a stationary states via their variational properties follows: the unsatisfactory aspects of the results add arguments in favor of the nonexistence of a function of state to be identified with entropy; at the same time new aspects and properties of the phase space contraction emerge.

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Giovanni Gallavotti. 2004-04-29. Entropy production in nonequilibrium thermodynamics: a review. https://doi.org/10.1063/1.1781911

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