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arXiv · 1711.01592

Local multiboson factorization of the quark determinant

Marco Cè·Leonardo Giusti·Stefan Schaefer
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Abstract

We discuss the recently proposed multiboson domain-decomposed factorization of the gauge-field dependence of the fermion determinant in lattice QCD. In particular, we focus on the case of a lattice divided in an arbitrary number of thick time slices. As a consequence, multiple space-time regions can be updated independently. This allows to address the exponential degradation of the signal-to-noise ration of correlation functions with multilevel Monte Carlo sampling. We show numerical evidence of the effectiveness of a two-level integration for pseudoscalar propagators with momentum and for vector propagators, in a two active regions setup. These results are relevant to lattice computation of the hadronic contributions to the anomalous magnetic moment of the muon and to heavy meson decay form factors.

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Marco Cè, Leonardo Giusti, Stefan Schaefer. 2017-11-05. Local multiboson factorization of the quark determinant. https://doi.org/10.1051/epjconf%2F201817511005

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