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arXiv · 1002.1842

Aging and fluctuation-dissipation ratio in a nonequilibrium $q$-state lattice model

M. O. Hase·T. Tomé·M. J. de Oliveira
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Abstract

A generalized version of the nonequilibrium linear Glauber model with $q$ states in $d$ dimensions is introduced and analyzed. The model is fully symmetric, its dynamics being invariant under all permutations of the $q$ states. Exact expressions for the two-time autocorrelation and response functions on a $d$-dimensional lattice are obtained. In the stationary regime, the fluctuation-dissipation theorem holds, while in the transient the aging is observed with the fluctuation-dissipation ratio leading to the value predicted for the linear Glauber model.

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M. O. Hase, T. Tomé, M. J. de Oliveira. 2010-02-09. Aging and fluctuation-dissipation ratio in a nonequilibrium $q$-state lattice model. https://doi.org/10.1103/physreve.82.011133

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