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Universal features of annealing and aging in compaction of granular piles.

ABSTRACT: This paper links the nonequilibrium glassy relaxation behavior of otherwise athermal granular materials to those of thermally activated glasses. Thus, it demonstrates a much wider universality among complex glassy materials out of equilibrium. Our three-dimensional molecular dynamics simulations, fully incorporating friction and inelastic collisions, are designed to reproduce experimental behavior of tapped granular piles. A simple theory based on a dynamics of records explains why the typical phenomenology of annealing and aging after a quench should extend to such granular matter, activated by taps, beyond the more familiar realm of polymers, colloids, and magnetic materials that all exhibit thermal fluctuations.

SUBMITTER: Gago PA

PROVIDER: S-EPMC7776891 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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Universal features of annealing and aging in compaction of granular piles.

Gago Paula A PA Boettcher Stefan S

Proceedings of the National Academy of Sciences of the United States of America 20201214 52

This paper links the nonequilibrium glassy relaxation behavior of otherwise athermal granular materials to those of thermally activated glasses. Thus, it demonstrates a much wider universality among complex glassy materials out of equilibrium. Our three-dimensional molecular dynamics simulations, fully incorporating friction and inelastic collisions, are designed to reproduce experimental behavior of tapped granular piles. A simple theory based on a dynamics of records explains why the typical p ...[more]

PMID: 33318185

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