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Updated: May 23, 2026

An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
Statistical mechanics of coarse graining: estimating dynamical speedups from excess entropies
J A Armstrong1, C Chakravarty, P Ballone
1School of Mathematics and Physics, Queen's University Belfast, Belfast BT7 1NN, United Kingdom.
Abstract:
The excess entropy of fluids has been shown to play a decisive role in the determination of dynamical properties [Y. Rosenfeld, Phys. Rev. A 15, 2545 (1977)]. We argue that it could play an equally important role in connecting dynamical properties of atomistic and coarse-grained models of molecular fluid systems. Molecular dynamics simulations for an atomistic and a coarse-grained model of water confirm the validity of this conjecture, showing that the sizable enhancement of the diffusion rate upon coarse-graining is a simple function of the difference in the excess entropy of the two models. This empirical observation could ease the way to a first-principles prediction of the relation of dynamical properties estimated from models at different resolution.
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