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arXiv · 1710.01975

Velocity gradient power functional for Brownian dynamics

Daniel de las Heras·Matthias Schmidt
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Abstract

We present an explicit and simple approximation for the superadiabatic excess (over ideal gas) free power functional, admitting the study of the nonequilibrium dynamics of overdamped Brownian many-body systems. The functional depends on the local velocity gradient and is systematically obtained from treating the microscopic stress distribution as a conjugate field. The resulting superadiabatic forces are beyond dynamical density functional theory and are of viscous nature. Their high accuracy is demonstrated by comparison to simulation results.

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Daniel de las Heras, Matthias Schmidt. 2017-10-05. Velocity gradient power functional for Brownian dynamics. https://doi.org/10.1103/physrevlett.120.028001

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