Correlations and critical behavior of the q-model

Alexander V. St. John; Harsh Mathur

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arXiv · 1108.2917

Correlations and critical behavior of the q-model

Alexander V. St. John·Harsh Mathur

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Abstract

The q-model is a random walk model used to describe the flow of stress in a stationary granular medium. Here we derive the exact horizontal and vertical correlation functions for the q-model in two dimensions. We show that close to a critical point identified in earlier work these correlation functions have a universal scaling form reminiscent of thermodynamic critical phenomena. We determine the form of the universal scaling function and the associated critical exponents $\nu$ and $z$.

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Alexander V. St. John, Harsh Mathur. 2011-08-15. Correlations and critical behavior of the q-model. https://arxiv.org/abs/1108.2917

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