2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/25906We 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.4 pages, 6 figures, submitted to the Proceedings of the conference "Powders and Grains 2005"Soft Condensed MatterStatistical Mechanicstext