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arXiv · hep-th/9604124

Renormalization of the Topological Charge in Yang-Mills Theory

M. Reuter
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Abstract

The conditions leading to a nontrivial renormalization of the topological charge in four--dimensional Yang--Mills theory are discussed. It is shown that if the topological term is regarded as the limit of a certain nontopological interaction, quantum effects due to the gauge bosons lead to a finite multiplicative renormalization of the theta--parameter while fermions give rise to an additional shift of theta. A truncated form of an exact renormalization group equation is used to study the scale dependence of the theta--parameter. Possible implications for the strong CP--problem of QCD are discussed.

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M. Reuter. 1996-04-20. Renormalization of the Topological Charge in Yang-Mills Theory. https://doi.org/10.1142/s0217732397002922

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