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arXiv · hep-th/9402077

Flow Equations and BRS Invariance for Yang-Mills Theories

Ulrich Ellwanger
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Abstract

Flow equations describe the evolution of the effective action $Γ_k$ in the process of varying an infrared cutoff $k$. The presence of the infrared cutoff explicitly breaks gauge and hence BRS invariance. We derive modified Slavnov-Taylor identities, which are valid for nonvanishing $k$. They guarantee the BRS invariance of $Γ_k$ for $k\to0$, and hence allow the study of non-abelian gauge theories by integrating the flow equations. Within a perturbative expansion of $Γ_k$, we derive an equation for a $k$ dependent mass term for the gauge fields implied by the modified Slavnov-Taylor identities.

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Ulrich Ellwanger. 1994-07-29. Flow Equations and BRS Invariance for Yang-Mills Theories. https://doi.org/10.1016/0370-2693(94)90365-4

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