English

Application of positivity bounds in asymptotically safe gravity

High Energy Physics - Theory 2024-05-16 v1 General Relativity and Quantum Cosmology High Energy Physics - Phenomenology

Abstract

Positivity bounds are bounds on the Wilson coefficients of an effective field theory. They hold, if the ultraviolet completion satisfies unitarity, microcausality, locality and Lorentz symmetry; accordingly their violation signals a violation of at least one of these properties of the ultraviolet completion. We explore whether positivity bounds on four-photon-couplings hold, when the ultraviolet completion is an asymptotically safe gravity-photon theory. By working at sixth order in an expansion in the electromagnetic field strength, we discover indications that positivity bounds hold for effective field theories that are UV completed by the asymptotically safe Reuter fixed point. We also perform various tests of the robustness of our result. This amounts to a nontrivial and critical indication of the physical viability of asymptotically safe gravity.

Keywords

Cite

@article{arxiv.2405.08862,
  title  = {Application of positivity bounds in asymptotically safe gravity},
  author = {Astrid Eichhorn and Andreas Odgaard Pedersen and Marc Schiffer},
  journal= {arXiv preprint arXiv:2405.08862},
  year   = {2024}
}

Comments

5 pages plus supplementary material; 2 figures plus 6 figures in supplementary material