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Self-organized criticality in nonconservative mean-field sandpiles

Dranreb Earl Juanico
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Abstract

A mean-field sandpile model that exhibits self-organized criticality (SOC) despite violation of the grain-transfer conservation law during avalanches is proposed. The sandpile consists of $N$ agents and possesses background activity with intensity $η\in[0,1]$. Background activity is characterized by transitions between two stable agent states. Analysis employing theories of branching processes and fixed points reveals a transition from sub-critical to SOC phase that is determined by $ηN$. The model is used to explain the school size distribution of free-swimming tuna as a result of population depletion.

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Dranreb Earl Juanico. 2007-02-09. Self-organized criticality in nonconservative mean-field sandpiles. https://arxiv.org/abs/nlin/0702019

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