Void or Dark Energy?

Understand

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.