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arXiv · 1207.6117

Non differentiable large-deviation functionals in boundary-driven diffusive systems

Guy Bunin·Yariv Kafri·Daniel Podolsky
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Abstract

We study the probability of arbitrary density profiles in conserving diffusive fields which are driven by the boundaries. We demonstrate the existence of singularities in the large-deviation functional, the direct analog of the free-energy in non-equilibrium systems. These singularities are unique to non-equilibrium systems and are a direct consequence of the breaking of time-reversal symmetry. This is demonstrated in an exactly-solvable model and also in numerical simulations on a boundary-driven Ising model. We argue that this singular behavior is expected to occur in models where the compressibility has a deep enough minimum. The mechanism is explained using a simple model.

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Guy Bunin, Yariv Kafri, Daniel Podolsky. 2012-07-25. Non differentiable large-deviation functionals in boundary-driven diffusive systems. https://doi.org/10.1088/1742-5468%2F2012%2F10%2Fl10001

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