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Multi-Step stochastic correction in dynamical fermion updating algorithms

Enno E. Scholz·Istvan Montvay
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Abstract

The advantages of using Multi-Step corrections for simulations of lattice gauge theories with dynamical fermions will be discussed. This technique is suited for algorithms based on the Multi-Boson representation of the dynamical fermions as well as for the Hybrid Monte-Carlo (HMC) algorithm and variants of the latter, like the Polynomial-HMC. Especially the latter has the power to deal with an odd number of fermion fields--an essential feature necessary for realistic QCD-simulations with up-, down-, and strange-quarks. In particular, we will discuss the application of the multi-step (actually two-step) correction technique to a PHMC updating algorithm for twisted-mass Wilson fermions with non-degenerate fermion masses, as it was used in recent dynamical simulations for N_f=2+1+1 fermion flavors.

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Enno E. Scholz, Istvan Montvay. 2006-10-20. Multi-Step stochastic correction in dynamical fermion updating algorithms. https://arxiv.org/abs/hep-lat/0609042

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