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arXiv · 1809.10587

Large-deviation theory for a Brownian particle on a ring: a WKB approach

Karel Proesmans·Bernard Derrida
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Abstract

We study the large deviation function of the displacement of a Brownian particle confined on a ring. In the zero noise limit this large deviation function has a cusp at zero velocity given by the Freidlin-Wentzell theory. We develop a WKB approach to analyse how this cusp is rounded in the weak noise limit.

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Karel Proesmans, Bernard Derrida. 2018-09-27. Large-deviation theory for a Brownian particle on a ring: a WKB approach. https://doi.org/10.1088/1742-5468/aafa7e

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