https://doi.org/10.1140/epjb/e20020099
Testing the Edwards hypothesis in spin systems under tapping dynamics
1
Institut für Theoretische Physik,
Universität zu Köln, Zülpicher Strasse 77,
50937 Köln, Germany
2
The Abdus Salam International Centre for Theoretical
Physics, Strada Costiera, 11 - 34100 Trieste, Italy
3
Service de Physique Théorique, CEA Saclay, 91191 Gif-sur-Yvette Cedex, France
4
Laboratoire de Physique, École Normale Supérieure de
Lyon and CNRS, 69007 Lyon, France
Corresponding author: a berg@thp.uni-koeln.de
Received:
30
November
2001
Published online: 15 April 2002
The Edwards hypothesis of ergodicity of blocked configurations for gently tapped granular materials is tested for abstract models of spin systems on random graphs and spin chains with kinetic constraints. The tapping dynamics is modeled by considering two distinct mechanisms of energy injection: thermal and random tapping. We find that ergodicity depends upon the tapping procedure (i.e. the way the blocked configurations are dynamically accessed): for thermal tapping ergodicity is a good approximation, while it fails to describe the asymptotic stationary state reached by the random tapping dynamics.
PACS: 05.70.Ln – Nonequilibrium and irreversible thermodynamics / 75.10.Nr – Spin-glass and other random models / 45.70.Cc – Static sandpiles; granular compaction
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2002