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arXiv · 1605.04886

The Derivation and Approximation of Coarse-grained Dynamics from Langevin Dynamics

Lina Ma·Xiantao Li·Chun Liu
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Abstract

We present a derivation of a coarse-grained model from the Langevin dynamics. The focus is placed on the memory kernel function and the fluctuation-dissipation theorem. Also presented is an hierarchy of approximations for the memory and random noise terms, using rational approximations in the Laplace domain. These approximations offer increasing accuracy. More importantly, they eliminate the need to evaluate the integral associated with the memory term at each time step.

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Lina Ma, Xiantao Li, Chun Liu. 2017-03-21. The Derivation and Approximation of Coarse-grained Dynamics from Langevin Dynamics. https://doi.org/10.1063/1.4967936

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