Reconciling cosmic dipolar tensions with a gigaparsec void

TL;DR

This paper proposes that a large-scale cosmic void can reconcile observed tensions between CMB and quasar dipoles and also ease the Hubble tension, challenging the standard cosmological principle.

Contribution

It introduces a model where living off-center in a gigaparsec void explains dipolar tensions and Hubble discrepancy, offering a new perspective on cosmic anisotropies.

Findings

A gigaparsec void can reconcile CMB and quasar dipolar tensions.

Living off-center affects dipolar anisotropies differently for quasars and CMB.

The model can also alleviate the Hubble tension.

Abstract

Recent observations indicate a $4.9\sigma$ tension between the CMB and quasar dipoles. This tension challenges the cosmological principle. We propose that if we live in a gigaparsec scale void, the CMB and quasar dipolar tension can be reconciled. This is because we are unlikely to live at the center of the void. And a within 10\% offset from the center will impact the quasars and CMB differently in their dipolar anisotropies. As we consider a large and thick void, our setup can also ease the Hubble tension.