Fluctuating Hydrodynamics Approach to Equilibrium Time Correlations for Anharmonic Chains

Abstract

Abstract. Linear fluctuating hydrodynamics is a useful and versatile tool for describing fluids, as well as other systems with conserved fields, on a mesoscopic scale. In one spatial dimension, however, transport is anomalous, which requires to develop a nonlinear extension of fluctuating hydrodynamics. The relevant nonlinearity turns out to be the quadratic part of the Euler currents when expanding relative to a uniform background. We outline the theory and compare with recent molecular dynamics simulations. 1 arXiv:1505.05987v2 [cond-mat.stat-mech]

Universal spatiotemporal scaling of distortions in a drifting lattice

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