Lessons from conformally reduced quantum gravity

TL;DR

This paper investigates an extended truncation of conformally reduced quantum gravity within the Asymptotic Safety framework, finding no evidence of an asymptotically safe fixed point beyond the Einstein-Hilbert approximation, and discusses broader implications for non-perturbative RG flows.

Contribution

It provides a comprehensive fixed point analysis of a large operator truncation in conformally reduced quantum gravity, revealing the absence of asymptotic safety in this setting.

Findings

No asymptotically safe fixed point beyond Einstein-Hilbert approximation

Extended operator truncation does not yield safety fixed points

Insights into non-perturbative renormalization group flows

Abstract

In this work we study a significantly enlarged truncation of conformally reduced quantum gravity in the context of Asymptotic Safety, including all operators that can be resolved in such a truncation including up to the sixth order in derivatives. A fixed point analysis suggests that there is no asymptotically safe fixed point in this system once one goes beyond an Einstein-Hilbert approximation. We will put these findings into context and discuss some lessons that can be learned from these results for general non-perturbative renormalisation group flows.