Can inhomogeneities solve the horizon problem ?

TL;DR

This paper explores how inhomogeneous cosmological models might explain the large-angle correlations in the CMB without requiring inflation, by analyzing photon propagation effects from the last scattering surface.

Contribution

It demonstrates that inhomogeneities alone can account for CMB anisotropies, challenging the necessity of inflationary models for this phenomenon.

Findings

Inhomogeneous models can reproduce observed CMB correlations.

Photon propagation effects in inhomogeneous universes explain large-angle anisotropies.

Inflation may not be essential for explaining CMB features.

Abstract

We show how inhomogeneous cosmological models can naturally explain the large angle correlation we observe in the CMB (cosmological microwave background) radiation without invoking any inflationary stage, but simply considering the effects of inhomogeneities on the propagation of photons from the last scattering surface.