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arXiv · 2302.07385

Transfer matrices and temporal factorization of the Wilson fermion determinant

Urs Wenger
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Abstract

When lattice QCD is formulated in sectors of fixed quark numbers, the canonical fermion determinants can be expressed explicitly in terms of transfer matrices. This in turn provides a complete factorization of the fermion determinants in temporal direction. Here we present a generic overview of this factorization, apply it to Wilson-type fermions and provide explicit constructions of the transfer matrices. Possible applications of the factorization include multi-level integration schemes and the construction of improved estimators for generic $n$-point correlation functions.

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Urs Wenger. 2023-02-14. Transfer matrices and temporal factorization of the Wilson fermion determinant. https://arxiv.org/abs/2302.07385

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