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Extreme events driven glassy behaviour in granular media

G. D'Anna·P. Mayor·G. Gremaud·A. Barrat·V. Loreto
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Abstract

Motivated by recent experiments on the approach to jamming of a weakly forced granular medium using an immersed torsion oscillator [Nature 413 (2001) 407], we propose a simple model which relates the microscopic dynamics to macroscopic rearrangements and accounts for the following experimental facts: (1) the control parameter is the spatial amplitude of the perturbation and not its reduced peak acceleration; (2) a Vogel-Fulcher-Tammann-like form for the relaxation time. The model draws a parallel between macroscopic rearrangements in the system and extreme events whose probability of occurrence (and thus the typical relaxation time) is estimated using extreme-value statistics. The range of validity of this description in terms of the control parameter is discussed as well as the existence of other regimes.

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G. D'Anna, P. Mayor, G. Gremaud, A. Barrat, V. Loreto. 2002-10-11. Extreme events driven glassy behaviour in granular media. https://doi.org/10.1209/epl%2Fi2003-00245-y

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