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arXiv · 1411.6163

Isometric fluctuation relations for equilibrium states with broken symmetry

D. Lacoste·P. Gaspard
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Abstract

We derive a set of isometric fluctuation relations, which constrain the order parameter fluctuations in finite-size systems at equilibrium and in the presence of a broken symmetry. These relations are exact and should apply generally to many condensed-matter physics systems. Here, we establish these relations for magnetic systems and nematic liquid crystals in a symmetry-breaking external field, and we illustrate them on the Curie-Weiss and the $XY$ models. Our relations also have implications for spontaneous symmetry breaking, which are discussed.

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BibTeXRIS

D. Lacoste, P. Gaspard. 2014-11-22. Isometric fluctuation relations for equilibrium states with broken symmetry. https://doi.org/10.1103/physrevlett.113.240602

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