A Maximally Symmetric Vector Propagator

TL;DR

This paper derives a de Sitter invariant propagator for massive vector fields that correctly reduces to flat spacetime and massless cases, facilitating quantum field theory calculations in curved spacetime.

Contribution

It provides the first explicit form of a maximally symmetric vector propagator on de Sitter space suitable for quantum computations.

Findings

Propagator is de Sitter invariant

Proper flat spacetime and massless limits achieved

Retarded Green's function yields correct classical response

Abstract

We derive the propagator for a massive vector field on a de Sitter background of arbitrary dimension. This propagator is de Sitter invariant and possesses the proper flat spacetime and massless limits. Moreover, the retarded Green's function inferred from it produces the correct classical response to a test source. Our result is expressed in a tensor basis which is convenient for performing quantum field theory computations using dimensional regularization.