Experimental measurement of an effective temperature for jammed granular materials

Chaoming Song, Ping Wang, Hernán A. Makse

Research output: Contribution to journalArticlepeer-review

83 Scopus citations


A densely packed granular system is an example of an out-of-equilibrium system in the jammed state. It has been a longstanding problem to determine whether this class of systems can be described by concepts arising from equilibrium statistical mechanics, such as an effective temperature and compactivity. The measurement of the effective temperature is realized in the laboratory by slowly shearing a closely packed ensemble of spherical beads confined by an external pressure in a Couette geometry. All of the probe particles considered in this study, independent of their characteristic features, equilibrate at the same temperature, given by the packing density of the system.

Original languageEnglish (US)
Pages (from-to)2299-2304
Number of pages6
JournalProceedings of the National Academy of Sciences of the United States of America
Issue number7
StatePublished - Feb 15 2005
Externally publishedYes


  • Granular matter
  • Jamming
  • Statistical mechanics of grains

ASJC Scopus subject areas

  • General


Dive into the research topics of 'Experimental measurement of an effective temperature for jammed granular materials'. Together they form a unique fingerprint.

Cite this