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Updated: Jun 2, 2026

An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
Chaotic versus nonchaotic stochastic dynamics in Monte Carlo simulations: a route for accurate energy differences in
Roland Assaraf1, Michel Caffarel, A C Kollias
1Laboratoire de Chimie Théorique, CNRS-UMR 7616 et Université Pierre et Marie Curie, 75252 Paris Cedex, France.
Abstract:
We present a method to efficiently evaluate small energy differences of two close N-body systems by employing stochastic processes having a stability versus chaos property. By using the same random noise, energy differences are computed from close trajectories without reweighting procedures. The approach is presented for quantum systems but can be applied to classical N-body systems as well. It is exemplified with diffusion Monte Carlo simulations for long chains of hydrogen atoms and molecules for which it is shown that the long-standing problem of computing energy derivatives is solved.
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