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arXiv · 2609.24462

Avalanche Size and Interevent Time Statistics in Amorphous System

Thomas Muhren·Roberto Benzi·Mauro Sbragaglia·Jeannot Trampert·Federico Toschi
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Abstract

The intermittent, stick-slip flow of amorphous systems is characterized by avalanches whose statistical properties display robust power-laws. In this paper, we study avalanche statistics in a field theoretical model of a soft-glassy system under shear. The order parameter in our model is the fluidity, which is related to the local rate of plastic events in a soft-glass. While avalanche sizes $S$ have been extensively characterized, the statistics of interevent times $t_i$ have remained largely unexplored. Here, we find that both $S$ and $t_i$ are power-law distributed and that their scaling exponents satisfy a precise relation. The model enables the analytical derivation of the scaling exponents and the reproduction of the behavior observed across a wide class of amorphous systems.

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Thomas Muhren, Roberto Benzi, Mauro Sbragaglia, Jeannot Trampert, Federico Toschi. 2026-09-21. Avalanche Size and Interevent Time Statistics in Amorphous System. https://arxiv.org/abs/2609.24462

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