Exact Renormalization Group and Running Newtonian Coupling in Higher Derivative Gravity

TL;DR

This paper investigates the exact renormalization group flow in higher derivative gravity, revealing how Newtonian coupling exhibits antiscreening or screening behavior depending on higher derivative couplings, using the effective average action formalism.

Contribution

It introduces a nonperturbative RG framework for $R^2$-gravity and derives coupled equations for gravitational couplings on De Sitter background, highlighting the behavior of Newtonian coupling.

Findings

Newtonian coupling shows antiscreening and screening behaviors

RG equations depend on higher derivative coupling constants

Approximate solutions reveal nonperturbative effects in higher derivative gravity

Abstract

We discuss exact renormalization group (RG) in $R^2$-gravity using effective average action formalism. The truncated evolution equation for such a theory on De Sitter background leads to the system of nonperturbative RG equations for cosmological and gravitational coupling constants. Approximate solution of these RG equations shows the appearence of antiscreening and screening behaviour of Newtonian coupling what depends on higher derivative coupling constants.