A note about the back-reaction of inhomogeneities on the expansion of the Universe

TL;DR

This paper discusses the debate on whether inhomogeneities in the universe significantly affect its expansion, concluding that current arguments suggest their impact on acceleration is minimal, using Fourier analysis of inhomogeneity power spectra.

Contribution

It provides a concise summary of the arguments against significant back-reaction and introduces a Fourier space method to evaluate inhomogeneity effects.

Findings

Arguments indicate minimal back-reaction impact on cosmic acceleration

Fourier space approach offers a quick assessment of inhomogeneity effects

Supports the view that inhomogeneities do not drive acceleration

Abstract

In this short note we summarize the arguments against a significant back-reaction of inhomogeneities on the acceleration of the Universe. We also present a quick way to access the importance of back-reaction using the Fourier space presentation of inhomogeneities and properties of their power spectrum.