Local quasi-equilibrium description of slow relaxation systems

I. Santamaria-Holek; A. Perez-Madrid; J. M. Rubi

doi:10.1063/1.1640346

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arXiv · cond-mat/0305605

Local quasi-equilibrium description of slow relaxation systems

I. Santamaria-Holek·A. Perez-Madrid·J. M. Rubi

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Abstract

We present a dynamical description of slow relaxation processes based on the extension of Onsager's fluctuation theory to systems in local quasi-equilibrium. A non-Markovian Fokker-Planck equation for the conditional probability density is derived and from it we obtain the relaxation equation for the moments. We show that the fluctuation-dissipation theorem can be formulated in terms of the temperature of the system at local quasi-equilibrium. Our theory may be applied to a wide variety of systems undergoing slow relaxation. We discuss in particular slow dynamics in glassy systems and Brownian motion in a granular gas.

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I. Santamaria-Holek, A. Perez-Madrid, J. M. Rubi. 2003-11-10. Local quasi-equilibrium description of slow relaxation systems. https://doi.org/10.1063/1.1640346

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