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arXiv · 2206.00974

Multilevel simulation of hard-sphere mixtures

Paul B. Rohrbach·Hideki Kobayashi·Robert Scheichl·Nigel B. Wilding·Robert L. Jack
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Abstract

We present a multilevel Monte Carlo simulation method for analysing multi-scale physical systems via a hierarchy of coarse-grained representations, to obtain numerically-exact results, at the most detailed level. We apply the method to a mixture of size-asymmetric hard spheres, in the grand canonical ensemble. A three-level version of the method is compared with a previously-studied two-level version. The extra level interpolates between the full mixture and a coarse-grained description where only the large particles are present -- this is achieved by restricting the small particles to regions close to the large ones. The three-level method improves the performance of the estimator, at fixed computational cost. We analyse the asymptotic variance of the estimator, and discuss the mechanisms for the improved performance.

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BibTeXRIS

Paul B. Rohrbach, Hideki Kobayashi, Robert Scheichl, Nigel B. Wilding, Robert L. Jack. 2022-06-02. Multilevel simulation of hard-sphere mixtures. https://doi.org/10.1063/5.0102875

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