Dynamic correlations in Brownian many-body systems

Joseph M. Brader; Matthias Schmidt

doi:10.1063/1.4861041

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arXiv · 1310.8257

Dynamic correlations in Brownian many-body systems

Joseph M. Brader·Matthias Schmidt

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Abstract

For classical Brownian systems driven out of equilibrium we derive inhomogeneous two-time correlation functions from functional differentiation of the one-body density and current with respect to external fields. In order to allow for appropriate freedom upon building the derivatives, we formally supplement the Smoluchowski dynamics by a source term, which vanishes at the physical solution. These techniques are applied to obtain a complete set of dynamic Ornstein-Zernike equations, which serve for the development of approximation schemes. The rules of functional calculus lead naturally to non-Markovian equations of motion for the two-time correlators. Memory functions are identified as functional derivatives of a unique space- and time-nonlocal dissipation power functional.

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Joseph M. Brader, Matthias Schmidt. 2014-01-17. Dynamic correlations in Brownian many-body systems. https://doi.org/10.1063/1.4861041

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