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Gauge invariance, background fields and modified Ward identities

F. Freire·D. F. Litim·J. M. Pawlowski
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Abstract

In this talk the gauge symmetry for Wilsonian flows in pure Yang-Mills theories is discussed. The background field formalism is used for the construction of a gauge invariant effective action. The symmetries of the effective action under gauge transformations for both the gauge field and the auxiliary background field are separately evaluated. Modified Ward-Takahashi and background field identities are used in my study. Finally it is shown how the symmetry properties of the full theory are restored in the limit where the cut-off is removed.

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F. Freire, D. F. Litim, J. M. Pawlowski. 2001-01-17. Gauge invariance, background fields and modified Ward identities. https://doi.org/10.1142/s0217751x01004669

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