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Effective temperature of an aging powder

M. Sellitto
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Abstract

The aging dynamics and the fluctuation-dissipation relation between the spontaneous diffusion induced by a random noise and the drift motion induced by a small stirring force are numerically investigated in a 3D schematic model of compacting powder: a gravity-driven lattice-gas with kinetic constraints. The compaction dynamics is characterized by a super-aging behaviour and, in analogy with glasses, exhibits a purely dynamical time-scale dependent effective temperature. A simple experiment to measure this quantity is suggested.

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M. Sellitto. 2001-04-26. Effective temperature of an aging powder. https://doi.org/10.1103/physreve.63.060301

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