Entropy production in the nonequilibrium steady states of interacting many-body systems

Entropy production is one of the most important characteristics of nonequilibrium steady states. We study here the steady-state entropy production, both at short times as well as in the long-time limit, of two important classes of nonequilibrium systems: transport systems and reaction-diffusion systems. The usefulness of the mean entropy production rate and of the large deviation function of the entropy production for characterizing nonequilibrium steady states of interacting many-body systems is discussed. We show that the large deviation function displays a kink-like feature at zero entropy production that is similar to that observed for a single particle driven along a periodic potential. This kink is a direct consequence of the detailed fluctuation theorem fulfilled by the probability distribution of the entropy production and is therefore a generic feature of the corresponding large deviation function.