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Effective Temperatures of a Driven System Near Jamming



I K. Ono, C S. O'Hern, Stephen A. Langer, A J. Liu, S R. Nagel, D J. Durian


Fluctuations in a model of a sheared, zero-temperature foam are studied numerically. Five different quantities that reduce to the true temperature in an equilibrium thermal system are calculated. All five have the same shear-rate dependence, and three have the same value. Near the onset of jamming, the relaxation time is the same function of these three temperatures in the sheared system as of the true temperature in an unsheared system. These results imply that statistical mechanics is useful for the system and provide strong support for the concept of jamming.
Physical Review Letters


foam, granular materials, jamming


Ono, I. , O'Hern, C. , Langer, S. , Liu, A. , Nagel, S. and Durian, D. (2002), Effective Temperatures of a Driven System Near Jamming, Physical Review Letters, [online], (Accessed December 8, 2023)
Created August 25, 2002, Updated October 12, 2021