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arXiv · hep-th/0404034

Topological effects in QCD and the problem of short-distance singularities

Martin Lüscher
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Abstract

The topological susceptibility and the higher moments of the topological charge distribution in QCD are expressed through certain n-point functions of the scalar and pseudo-scalar quark densities at vanishing momenta, which are free of short-distance singularities. Since the normalization of the correlation functions is determined by the non-singlet chiral Ward identities, these formulae provide an unambiguous regularization-independent definition of the moments and thus of the charge distribution.

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Martin Lüscher. 2004-06-01. Topological effects in QCD and the problem of short-distance singularities. https://doi.org/10.1016/j.physletb.2004.04.076

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