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arXiv · 2210.09328

Perturbative running of the topological angles

Alessandro Valenti·Luca Vecchi
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Abstract

We argue that in general renormalizable field theories the topological angles may develop an additive beta function starting no earlier than 2-loop order. The leading expression is uniquely determined by a single model-independent coefficient. The associated divergent diagrams are identified and a few independent methods for extracting the beta function in dimensional regularization are discussed. We show that the peculiar nature of the topological angles implies non-trivial constraints on the anomalous dimension of the CP-violating operators and discuss how a non-vanishing beta function affects the Weyl consistency conditions. Some phenomenological considerations are presented.

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Alessandro Valenti, Luca Vecchi. 2023-01-20. Perturbative running of the topological angles. https://doi.org/10.1007/jhep01(2023)131

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