Force correlations in the q-model for general q-distributions

Jacco H. Snoeijer; J. M. J. van Leeuwen

doi:10.1103/physreve.65.051306

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Force correlations in the q-model for general q-distributions

Jacco H. Snoeijer·J. M. J. van Leeuwen

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Abstract

We study force correlations in the q-model for granular media at infinite depth, for general q-distributions. We show that there are no 2-point force correlations as long as q-values at different sites are uncorrelated. However, higher order correlations can persist, and if they do, they only decay with a power of the distance. Furthermore, we find the entire set of q-distributions for which the force distribution factorizes. It includes distributions ranging from infinitely sharp to almost critical. Finally, we show that 2-point force correlations do appear whenever there are correlations between q-values at different sites in a layer; various cases are evaluated explicitly.

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BibTeX RIS

Jacco H. Snoeijer, J. M. J. van Leeuwen. 2002-02-07. Force correlations in the q-model for general q-distributions. https://doi.org/10.1103/physreve.65.051306

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