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arXiv · 0705.2344

Canonical structure of dynamical fluctuations in mesoscopic nonequilibrium steady states

Christian Maes·Karel Netočný
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Abstract

We give the explicit structure of the functional governing the dynamical density and current fluctuations for a mesoscopic system in a nonequilibrium steady state. Its canonical form determines a generalised Onsager-Machlup theory. We assume that the system is described as a Markov jump process satisfying a local detailed balance condition such as typical for stochastic lattice gases and for chemical networks. We identify the entropy current and the traffic between the mesoscopic states as extra terms in the fluctuation functional with respect to the equilibrium dynamics. The density and current fluctuations are coupled in general, except close to equilibrium where their decoupling explains the validity of entropy production principles.

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Christian Maes, Karel Netočný. 2007-05-16. Canonical structure of dynamical fluctuations in mesoscopic nonequilibrium steady states. https://doi.org/10.1209/0295-5075/82/30003

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