Impact of cosmic inhomogeneities on SNe observations

TL;DR

This paper investigates how cosmic inhomogeneities, like local voids and lensing effects, influence supernova observations and their interpretation, proposing a model that mimics the standard cosmological model.

Contribution

It introduces a combined inhomogeneous universe model that accounts for local voids and lensing, aligning supernova data with the Copernican Principle.

Findings

The model can replicate the concordance cosmological model.

Local voids cause apparent acceleration at low redshifts.

Lensing effects from voids impact high-redshift supernova brightness.

Abstract

We study the impact of cosmic inhomogeneities on the interpretation of SNe observations. We build an inhomogeneous universe model that can confront supernova data and yet is reasonably well compatible with the Copernican Principle. Our model combines a relatively small local void, that gives apparent acceleration at low redshifts, with a meatball model that gives sizeable lensing (dimming) at high redshifts. Together these two elements, which focus on different effects of voids on the data, allow the model to mimic the concordance model.