Asymptotic Safety in Lorentzian quantum gravity

TL;DR

This paper demonstrates that a functional renormalization group approach applied to Lorentzian quantum gravity reveals a non-trivial fixed point, supporting the Asymptotic Safety scenario in a Lorentzian spacetime context.

Contribution

It introduces a new RG equation for Lorentzian quantum gravity and shows the existence of a universal fixed point indicating Asymptotic Safety.

Findings

Existence of a non-trivial fixed point in Lorentzian quantum gravity

Universal contributions to the RG flow are state and background independent

Supports Asymptotic Safety as a viable quantum gravity approach

Abstract

We report on a recently introduced Functional Renormalization Group (RG) Equation, and we apply it to quantum gravity in Lorentzian spacetimes. While the RG flow is state-dependent, it is possible to evaluate state and background independent contributions to the flow. Taking into account only these universal terms, the RG flow exhibits a non-trivial fixed point in the Einstein-Hilbert truncation, providing a mechanism for Asymptotic Safety in Lorentzian quantum gravity.