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Updated: Jun 1, 2026

An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
Anomalies and absence of local equilibrium, and universality, in one-dimensional particles systems
1Dipartimento di Scienze e Metodi dell'Ingegneria, Università di Modena e Reggio E., Via Amendola 2, Pad. Morselli, I-42122 Reggio E., Italy. claudio.giberti@unimore.it
Abstract:
One-dimensional systems are under intense investigation, both from theoretical and experimental points of view, since they have rather peculiar characteristics which are of both conceptual and technological interest. We analyze the dependence of the behavior of one-dimensional, time-reversal invariant, nonequilibrium systems on the parameters defining their microscopic dynamics. In particular, we consider chains of identical oscillators interacting via hard-core elastic collisions and harmonic potentials, driven by boundary Nosé-Hoover thermostats. Their behavior mirrors qualitatively that of stochastically driven systems, showing that anomalous properties are typical of physics in one dimension. Chaos, by itself, does not lead to standard behavior, since it does not guarantee local thermodynamic equilibrium. A linear relation is found between density fluctuations and temperature profiles. This link and the temporal asymmetry of fluctuations of the main observables are robust against modifications of thermostat parameters and against perturbations of the dynamics.
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