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Free volume distributions inside a bidimensional granular medium

F. da Cruz·F. Lechenault·O. Dauchot·E. Bertin
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Abstract

We investigate experimentally within a two-dimensional cell the distribution of the free volume associated either to single grains or to clusters of grains. Our main result is that the logarithm of the probability to find a free volume per grain v_N^f in a cluster of N grains scales as N^alpha g(v_N^f), with alpha = 0.75. We interpret this non extensive scaling factor N^alpha as an evidence for the onset of long range correlations between the free volumes of individual grains. We also discuss the possible relation between g(v_N^f) and Edwards entropy.

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F. da Cruz, F. Lechenault, O. Dauchot, E. Bertin. 2005-02-21. Free volume distributions inside a bidimensional granular medium. https://arxiv.org/abs/cond-mat/0502504

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