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arXiv · 2303.01479

A Lorentzian renormalisation group equation for gauge theories

Edoardo D'Angelo·Kasia Rejzner
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Abstract

In a recent paper, with Drago and Pinamonti we have introduced a Wetterich-type flow equation for scalar fields on Lorentzian manifolds, using the algebraic approach to perturbative QFT. The equation governs the flow of the effective average action, under changes of a mass parameter k. Here we introduce an analogous flow equation for gauge theories, with the aid of the Batalin-Vilkovisky (BV) formalism. We also show that the corresponding effective average action satisfies a Slavnov-Taylor identity in Zinn-Justin form. We interpret the equation as a cohomological constraint on the functional form of the effective average action, and we show that it is consistent with the flow.

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Edoardo D'Angelo, Kasia Rejzner. 2023-03-02. A Lorentzian renormalisation group equation for gauge theories. https://doi.org/10.1007/s00023-024-01535-x

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