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Updated: Aug 20, 2026

An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
Temperature in nonequilibrium systems with conserved energy
Eric Bertin1, Olivier Dauchot, Michel Droz
1Department of Theoretical Physics, University of Geneva, CH-1211 Geneva 4, Switzerland.
Abstract:
We study a class of nonequilibrium lattice models which describe local redistributions of a globally conserved energy. A particular subclass can be solved analytically, allowing us to define a temperature T(th) along the same lines as in the equilibrium microcanonical ensemble. The fluctuation-dissipation relation is explicitly found to be linear, but its slope differs from the inverse temperature T(-1)(th). A numerical renormalization group procedure suggests that, at a coarse-grained level, all models behave similarly, leading to a two-parameter description of their macroscopic properties.
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