Asymptotic Safety: Swampland or Wonderland?

TL;DR

This paper explores the compatibility of asymptotic safety in gravity with various swampland conjectures, revealing a complex interplay that constrains the parameter space of consistent theories of quantum gravity.

Contribution

It combines asymptotic safety and swampland conjectures to analyze the allowed parameter space in quantum gravity, identifying intersections and constraints.

Findings

Overlap region between asymptotic safety and swampland conjectures is a proper subspace.

The hypersurface of asymptotic safety lies within the weak gravity conjecture's allowed region.

Interplay suggests constraints from UV completeness, black hole physics, and cosmology.

Abstract

We investigate the consequences of combining swampland conjectures with the requirement of asymptotic safety. To this end, we explore the infrared regime of asymptotically safe gravity in the quadratic one-loop approximation, and we identify the hypersurface spanned by the endpoints of asymptotically safe renormalization group trajectories. These comprise the allowed values of higher-derivative couplings as well as standard logarithmic form factors. We determine the intersection of this hypersurface with the regions of parameter space allowed by the weak-gravity conjecture, the swampland de Sitter conjecture, and the trans-Planckian censorship conjecture. The latter two depend on some order-one constants, for generic values of which we show that the overlap region is a proper subspace of the asymptotically safe hypersurface. Moreover, the latter lies inside the region allowed by the weak gravity conjecture assuming electromagnetic duality. Our results suggest a non-trivial interplay between the consistency conditions stemming from ultraviolet completeness of the RG flow, black hole physics, and cosmology.