Exact predictions from Edwards ensemble vs. realistic simulations of tapped narrow two-dimensional granular columns

Bibliographic Details
Title: Exact predictions from Edwards ensemble vs. realistic simulations of tapped narrow two-dimensional granular columns
Authors: Irastorza, Ramiro M., Carlevaro, C. Manuel, Pugnaloni, Luis A.
Publication Year: 2013
Collection: Condensed Matter
Subject Terms: Condensed Matter - Soft Condensed Matter
More Details: We simulate via a Discrete Element Method the tapping of a narrow column of disk under gravity. For frictionless disks, this system has a simple analytic expression for the density of states in the Edwards volume ensemble. We compare the predictions of the ensemble at constant compactivity against the results for the steady states obtained in the simulations. We show that the steady states cannot be properly described since the microstates sampled are not in correspondence with the predicted distributions, suggesting that the postulates of flat measure and ergodicity are, either or both, invalid for this simple realization of a static granular system. However, we show that certain qualitative features of the volume fluctuations difficult to predict from simple arguments are captured by the theory.
Comment: 11 pages, 6 figures
Document Type: Working Paper
DOI: 10.1088/1742-5468/2013/12/P12012
Access URL: http://arxiv.org/abs/1311.1069
Accession Number: edsarx.1311.1069
Database: arXiv
More Details
DOI:10.1088/1742-5468/2013/12/P12012