An exact Polynomial Hybrid Monte Carlo algorithm for dynamical Kogut-Susskind fermions

JLQCD Collaboration; K-I. Ishikawa; M. Fukugita; S. Hashimoto; N. Ishizuka; Y. Iwasaki; K. Kanaya; Y. Kuramashi; M. Okawa; N. Tsutsui; A. Ukawa; N. Yamada; T. Yoshié

arXiv · hep-lat/0209061

An exact Polynomial Hybrid Monte Carlo algorithm for dynamical Kogut-Susskind fermions

JLQCD Collaboration·K-I. Ishikawa·M. Fukugita·S. Hashimoto·N. Ishizuka·Y. Iwasaki·K. Kanaya·Y. Kuramashi·M. Okawa·N. Tsutsui·A. Ukawa·N. Yamada·T. Yoshié

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Abstract

We present a polynomial Hybrid Monte Carlo (PHMC) algorithm as an exact simulation algorithm with dynamical Kogut-Susskind fermions. The algorithm uses a Hermitian polynomial approximation for the fractional power of the KS fermion matrix. The systematic error from the polynomial approximation is removed by the Kennedy-Kuti noisy Metropolis test so that the algorithm becomes exact at a finite molecular dynamics step size. We performed numerical tests with $N_f$$=$2 case on several lattice sizes. We found that the PHMC algorithm works on a moderately large lattice of $16^4$ at $β$$=$5.7, $m$$=$0.02 ($m_{\mathrm{PS}}/m_{\mathrm{V}}$$\sim$0.69) with a reasonable computational time.

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JLQCD Collaboration, K-I. Ishikawa, M. Fukugita, S. Hashimoto, N. Ishizuka, Y. Iwasaki, K. Kanaya, Y. Kuramashi, M. Okawa, N. Tsutsui, A. Ukawa, N. Yamada, T. Yoshié. 2002-09-04. An exact Polynomial Hybrid Monte Carlo algorithm for dynamical Kogut-Susskind fermions. https://arxiv.org/abs/hep-lat/0209061

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