The covariant graviton propagator in de Sitter spacetime

TL;DR

This paper derives an explicit form of the covariant graviton propagator in de Sitter spacetime, demonstrating that gauge-invariant two-point functions remain bounded at large separations, which has implications for quantum gravity in cosmological settings.

Contribution

It provides an explicit expression for the graviton propagator in de Sitter space with a specific gauge choice, extending previous work by including arbitrary gauge parameters.

Findings

Two-point functions of gauge-invariant quantities do not grow with distance.

Explicit form of the graviton propagator in a particular gauge.

Confirmation of bounded behavior of gauge-invariant correlators at large separations.

Abstract

We consider the covariant graviton propagator in de Sitter spacetime in a gauge with two parameters, alpha and beta, in the Euclidean approach. We give an explicit form of the propagator with a particular choice of beta but with arbitrary value of alpha. We confirm that two-point functions of local gauge-invariant quantities do not increase as the separation of the two points becomes large.