More on the covariant retarded Green's function for the electromagnetic field in de Sitter spacetime

TL;DR

This paper extends previous work demonstrating that covariant retarded Green's functions can accurately reproduce electromagnetic fields in de Sitter spacetime, even with arbitrary gauge parameters, using a two-charge model.

Contribution

It shows that the covariant retarded Green's function with any gauge parameter correctly reproduces electromagnetic fields from antipodal charges in de Sitter space.

Findings

Green's function reproduces fields for arbitrary gauge parameters

Validates approach with antipodal charge configuration

Extends previous results to more general gauges

Abstract

In a recent paper (Phys. Rev. D78, 084031 (2008), arXiv:0808.0642, Ref. [1]) it was shown in examples that the covariant retarded Green's functions in particular gauges for electromagnetism and linearized gravity can be used to reproduce field configurations correctly in spite of the spacelike nature of past infinity in de Sitter spacetime. In this paper we extend the work of Ref. [1] concerning the electromagnetic field and show that the covariant retarded Green's function with an arbitrary value of the gauge parameter reproduces the electromagnetic field from two opposite charges at antipodal points of de Sitter spacetime.