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arXiv · 2009.03255

Functional Renormalization and $\overline{\text{MS}}$

Alessio Baldazzi·Roberto Percacci·Luca Zambelli
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Abstract

Working with scalar field theories, we discuss choices of regulator that, inserted in the functional renormalization group equation, reproduce the results of dimensional regularization at one and two loops. The resulting flow equations can be seen as nonperturbative extensions of the $\overline{\text{MS}}\,$ scheme. We support this claim by recovering all the multicritical models in two dimensions. We discuss a possible generalization to any dimension. Finally, we show that the method also preserves nonlinearly realized symmetries, which is a definite advantage with respect to other regulators.

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Alessio Baldazzi, Roberto Percacci, Luca Zambelli. 2020-09-07. Functional Renormalization and $\overline{\text{MS}}$. https://doi.org/10.1103/physrevd.103.076012

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