Void or Dark Energy?

TL;DR

This paper compares the void model and dark energy explanation for supernova observations, highlighting that the void scenario can explain the data without invoking unseen dark energy, but both face fine-tuning issues.

Contribution

It argues that a nonlinear underdense void can account for supernova data without dark energy, challenging the standard $ ext{Λ}$CDM model.

Findings

Void model explains supernova data without dark energy.

Both models face fine-tuning problems.

Void scenario avoids introducing undetected dark energy.

Abstract

Two possible explanations for the type SNe Ia supernovae observations are a nonlinear, underdense void embedded in a matter-dominated Einstein-de Sitter spacetime or dark energy in the $\Lambda$CDM model. Both of these alternatives are faced with Copernican fine-tuning problems. A case is made for the void scenario that avoids introducing undetected dark energy.