How Inflationary Gravitons Affect the Force of Gravity

TL;DR

This paper investigates how quantum effects of gravitons in de Sitter space modify the classical Newtonian potential, revealing significant logarithmic corrections that challenge perturbation theory at large scales and late times.

Contribution

It provides a novel calculation of quantum corrections to gravity from gravitons on de Sitter background, highlighting the impact of large logarithms on gravitational potentials.

Findings

Large spatial and temporal logarithmic corrections to Newtonian potential.

Gravitons induce up to three large logarithms, more than scalar loops.

Perturbation theory breaks down at large distances and late times due to these corrections.

Abstract

We employ an unregulated computation the graviton self-energy from gravitons on de Sitter background to infer the renormalized result. This is used to quantum-correct the linearized Einstein equation. We solve this equation for the potentials which represent the gravitational response to static, point mass. We find large spatial and temporal logarithmic corrections to the Newtonian potential and to the gravitational shift. Although suppressed by a minuscule loop-counting parameter, these corrections cause perturbation theory to break down at large distances and late times. Another interesting fact is that gravitons induce up to three large logarithms whereas a loop of massless, minimally coupled scalars produces only a single large logarithm. This is in line with corrections to the graviton mode function: a loop of gravitons induces two large logarithms whereas a scalar loop gives none.