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arXiv · 1302.5246

Chiral symmetry and the Yang--Mills gradient flow

Martin Lüscher
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Abstract

In the last few years, the Yang--Mills gradient flow was shown to be an attractive tool for non-perturbative studies of non-Abelian gauge theories. Here a simple extension of the flow to the quark fields in QCD is considered. As in the case of the pure-gauge gradient flow, the renormalizability of correlation functions involving local fields at positive flow times can be established using a representation through a local field theory in 4+1 dimensions. Applications of the extended flow in lattice QCD include non-perturbative renormalization and O(a) improvement as well as accurate calculations of the chiral condensate and of the pseudo-scalar decay constant in the chiral limit.

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Martin Lüscher. 2013-06-17. Chiral symmetry and the Yang--Mills gradient flow. https://doi.org/10.1007/jhep04(2013)123

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