Higher Derivative Gravity from the Universal Renormalization Group Machine

TL;DR

This paper investigates the renormalization group flow in higher derivative gravity using a novel computational algorithm, revealing universal features and scheme-dependent fixed points in the beta-functions.

Contribution

It introduces the universal renormalization group machine algorithm to solve flow equations and analyzes the scheme dependence of fixed points in higher derivative gravity.

Findings

Universal features of one-loop beta-functions are recovered.

One fixed point's existence depends on the regularization scheme.

The other fixed point appears scheme-independent and potentially physical.

Abstract

We study the renormalization group flow of higher derivative gravity, utilizing the functional renormalization group equation for the average action. Employing a recently proposed algorithm, termed the universal renormalization group machine, for solving the flow equation, all the universal features of the one-loop beta-functions are recovered. While the universal part of the beta-functions admits two fixed points, we explicitly show that the existence of one of them depends on the choice of regularization scheme, indicating that it is most probably unphysical.