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On random graphs and the statistical mechanics of granular matter

Johannes Berg·Anita Mehta
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Abstract

The dynamics of spins on a random graph with ferromagnetic three-spin interactions is used to model the compaction of granular matter under a series of taps. Taps are modelled as the random flipping of a small fraction of the spins followed by a quench at zero temperature. We find that the density approached during a logarithmically slow compaction - the random-close-packing density - corresponds to a dynamical phase transition. We discuss the the role of cascades of successive spin-flips in this model and link them with density-noise power fluctuations observed in recent experiments.

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Johannes Berg, Anita Mehta. 2001-10-19. On random graphs and the statistical mechanics of granular matter. https://doi.org/10.1209/epl%2Fi2001-00588-3

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