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Universality classes for rice-pile models

L. A. N. Amaral·K. B. Lauritsen
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Abstract

We investigate sandpile models where the updating of unstable columns is done according to a stochastic rule. We examine the effect of introducing nonlocal relaxation mechanisms. We find that the models self-organize into critical states that belong to three different universality classes. The models with local relaxation rules belong to a known universality class that is characterized by an avalanche exponent $τ\approx 1.55$, whereas the models with nonlocal relaxation rules belong to new universality classes characterized by exponents $τ\approx 1.35$ and $τ\approx 1.63$. We discuss the values of the exponents in terms of scaling relations and a mapping of the sandpile models to interface models.

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L. A. N. Amaral, K. B. Lauritsen. 1997-05-11. Universality classes for rice-pile models. https://doi.org/10.1103/physreve.56.231

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