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arXiv · 2201.02457

Position-dependent memory kernel in generalized Langevin equations: theory and numerical estimation

Hadrien Vroylandt·Pierre Monmarché
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Abstract

Generalized Langevin equations with non-linear forces and position-dependent linear friction memory kernels, such as commonly used to describe the effective dynamics of coarse-grained variables in molecular dynamics, are rigorously derived within the Mori-Zwanzig formalism. A fluctuation-dissipation theorem relating the properties of the noise to the memory kernel is shown. The derivation also yields Volterra-type equations for the kernel, which can be used for a numerical parametrization of the model from all-atom simulations.

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BibTeXRIS

Hadrien Vroylandt, Pierre Monmarché. 2022-01-07. Position-dependent memory kernel in generalized Langevin equations: theory and numerical estimation. https://doi.org/10.1063/5.0094566

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