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arXiv · 2107.03839

The weak-gravity bound and the need for spin in asymptotically safe matter-gravity models

Gustavo P. de Brito·Astrid Eichhorn·Rafael Robson Lino dos Santos
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Abstract

We discover a weak-gravity bound in scalar-gravity systems in the asymptotic-safety paradigm. The weak-gravity bound arises in these systems under the approximations we make, when gravitational fluctuations exceed a critical strength. Beyond this critical strength, gravitational fluctuations can generate complex fixed-point values in higher-order scalar interactions. Asymptotic safety can thus only be realized at sufficiently weak gravitational interactions. We find that within truncations of the matter-gravity dynamics, the fixed point lies beyond the critical strength, unless spinning matter, i.e., fermions and vectors, is also included in the model.

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Gustavo P. de Brito, Astrid Eichhorn, Rafael Robson Lino dos Santos. 2021-07-08. The weak-gravity bound and the need for spin in asymptotically safe matter-gravity models. https://doi.org/10.1007/jhep11(2021)110

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