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arXiv · 1811.03615

BRST invariant RG flows

Shimasadat Asnafi·Holger Gies·Luca Zambelli
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Abstract

A mass parameter for the gauge bosons in gauge-fixed four-dimensional Yang-Mills theory can be accommodated in a local and manifestly BRST-invariant action. The construction is based on the Faddeev-Popov method involving a nonlinear gauge-fixing and a background Nakanishi-Lautrup field. When applied to momentum-dependent masslike deformations, this formalism leads to a full regularization of the theory which explicitly preserves BRST symmetry. We deduce a functional renormalization group equation for the one-particle-irreducible effective action, which has a one-loop form. The master equation is compatible with it, i.e. BRST symmetry is preserved along the flow, and it has a standard regulator-independent Zinn-Justin form. As a first application, we compute the leading-order gluon wave-function renormalization.

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Shimasadat Asnafi, Holger Gies, Luca Zambelli. 2018-11-08. BRST invariant RG flows. https://doi.org/10.1103/physrevd.99.085009

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