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arXiv · hep-lat/0303026

Accelerating the Hybrid Monte Carlo algorithm

A. Ali Khan·T. Bakeyev·M. Göckeler·R. Horsley·D. Pleiter·P. Rakow·A. Schäfer·G. Schierholz·H. Stüben
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Abstract

An algorithm for separating the high- and low-frequency molecular dynamics modes in Hybrid Monte Carlo simulations of gauge theories with dynamical fermions is presented. The separation is based on splitting the pseudo-fermion action into two parts, as was initially proposed by Hasenbusch. We propose to introduce different evolution time-scales for each part. We test our proposal in realistic simulations of two-flavor O(a) improved Wilson fermions. A speed-up of more than a factor of three compared to the standard HMC algorithm is observed in a typical run.

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A. Ali Khan, T. Bakeyev, M. Göckeler, R. Horsley, D. Pleiter, P. Rakow, A. Schäfer, G. Schierholz, H. Stüben. 2003-03-28. Accelerating the Hybrid Monte Carlo algorithm. https://doi.org/10.1016/s0370-2693(03)00703-2

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