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arXiv · 2501.10307

Asymptotic safety meets tensor field theory: towards a new class of gravity-matter systems

Astrid Eichhorn·Razvan Gurau·Zois Gyftopoulos
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Abstract

Combining asymptotically safe quantum gravity with a tensor field theory, we exhibit the first example of a theory with gravity and scalar fields in four dimensions which may realize asymptotic safety at a non-vanishing value of the scalar quartic coupling. We first present (further) evidence that in the asymptotic-safety paradigm, quantum fluctuations of gravity generically screen the quartic couplings in (multi-)scalar models. For a tensor field theory in which the scalar field transforms under an internal $O(N)^3$ symmetry, this has the effect of replacing asymptotic freedom, recently discovered at large $N$ on a fixed flat background, by an interacting fixed point in the presence of quantum gravity. The fixed point originates from the competition between the effects of the matter self-interactions which, contrary to the usual scalar models, are antiscreening, and the screening gravitational effects.

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Astrid Eichhorn, Razvan Gurau, Zois Gyftopoulos. 2025-01-17. Asymptotic safety meets tensor field theory: towards a new class of gravity-matter systems. https://arxiv.org/abs/2501.10307

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