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Glassy dynamics in granular compaction: sand on random graphs

Johannes Berg·Anita Mehta
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Abstract

We discuss the use of a ferromagnetic spin model on a random graph to model granular compaction. A multi-spin interaction is used to capture the competition between local and global satisfaction of constraints characteristic for geometric frustration. We define an athermal dynamics designed to model repeated taps of a given strength. Amplitude cycling and the effect of permanently constraining a subset of the spins at a given amplitude is discussed. Finally we check the validity of Edwards' hypothesis for the athermal tapping dynamics.

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Johannes Berg, Anita Mehta. 2001-10-19. Glassy dynamics in granular compaction: sand on random graphs. https://doi.org/10.1103/physreve.65.031305

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