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Off-equilibrium dynamics in a singular diffusion model

Federico Corberi·Mario Nicodemi·Marina Piccioni·Antonio Coniglio
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Abstract

We introduce a schematic non-linear diffusion model where density fluctuations induce a rich out of equilibrium dynamics. The properties of the model are studied by numerical simulations and analytically in a mean field approximation. At low temperatures and high densities we find a long off-equilibrium glassy region, where the system evolves out of an initially pinned state showing aging and a slow decay of the autocorrelation as an enhanced power law, along with strong spatial heterogeneities and violation of the fluctuation dissipation theorem.

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Federico Corberi, Mario Nicodemi, Marina Piccioni, Antonio Coniglio. 1999-10-27. Off-equilibrium dynamics in a singular diffusion model. https://doi.org/10.1103/physrevlett.83.5054

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