Vector and Tensor Contributions to the Luminosity Distance

TL;DR

This paper develops a formalism to compute how vector and tensor perturbations, including primordial gravitational waves, affect the luminosity distance measurements in cosmology, expanding the analysis in spherical harmonics.

Contribution

It introduces a new formalism for vector and tensor contributions to luminosity distance fluctuations and applies it to primordial gravitational waves.

Findings

Formalism for vector and tensor effects on luminosity distance.

Application to primordial gravitational wave background.

Enhanced understanding of gravitational wave impact on cosmological observations.

Abstract

We compute the vector and tensor contributions to the luminosity distance fluctuations in first order perturbation theory and we expand them in spherical harmonics. This work presents the formalism with a first application to a stochastic background of primordial gravitational waves.