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arXiv · 0809.3966

Test of the Additivity Principle for Current Fluctuations in a Model of Heat Conduction

Pablo I. Hurtado·Pedro L. Garrido
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Abstract

The additivity principle allows to compute the current distribution in many one-dimensional (1D) nonequilibrium systems. Using simulations, we confirm this conjecture in the 1D Kipnis-Marchioro-Presutti model of heat conduction for a wide current interval. The current distribution shows both Gaussian and non-Gaussian regimes, and obeys the Gallavotti-Cohen fluctuation theorem. We verify the existence of a well-defined temperature profile associated to a given current fluctuation. This profile is independent of the sign of the current, and this symmetry extends to higher-order profiles and spatial correlations. We also show that finite-time joint fluctuations of the current and the profile are described by the additivity functional. These results suggest the additivity hypothesis as a general and powerful tool to compute current distributions in many nonequilibrium systems.

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Pablo I. Hurtado, Pedro L. Garrido. 2008-09-23. Test of the Additivity Principle for Current Fluctuations in a Model of Heat Conduction. https://doi.org/10.1103/physrevlett.102.250601

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