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arXiv · 1305.3839

Nonequilibrium Ornstein-Zernike relation for Brownian many-body dynamics

Joseph M. Brader·Matthias Schmidt
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Abstract

We derive a dynamic Ornstein-Zernike equation for classical fluids undergoing overdamped Brownian motion and driven out of equilibrium. Inhomogeneous two-time correlation functions are obtained from functional differentiation of the one-body density and current with respect to an appropriately chosen external field. Functional calculus leads naturally to non-Markovian equations of motion for the two-time correlators. Memory functions are identified as functional derivatives of a space- and time-nonlocal power dissipation functional. We propose an excess (over ideal gas) dissipation functional that both generates mode-coupling theory for the two-body correlations and extends dynamical density functional theory for the one-body fields, thus unifying the two approaches.

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Joseph M. Brader, Matthias Schmidt. 2013-05-16. Nonequilibrium Ornstein-Zernike relation for Brownian many-body dynamics. https://doi.org/10.1063/1.4820399

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