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arXiv · 2207.06749

Evidence for a novel shift-symmetric universality class from the functional renormalization group

Cristobal Laporte·Nora Locht·Antonio D. Pereira·Frank Saueressig
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Abstract

Wetterich's equation provides a powerful tool for investigating the existence and universal properties of renormalization group fixed points exhibiting quantum scale invariance. Motivated by recent works on asymptotically safe scalar-tensor theories, we develop a novel approximation scheme which projects the functional renormalization group equation onto functions of the kinetic term. Applying this projection to scalars and gauge fields, our analysis identifies a new universality class with a very special spectrum of stability coefficients. The implications of our findings in the context of asymptotically safe gravity-matter systems are discussed.

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Cristobal Laporte, Nora Locht, Antonio D. Pereira, Frank Saueressig. 2022-07-14. Evidence for a novel shift-symmetric universality class from the functional renormalization group. https://doi.org/10.1016/j.physletb.2022.137666

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