Resolving the Planck-DESI tension by nonminimally coupled quintessence

TL;DR

This paper proposes a nonminimally coupled quintessence model to resolve the matter fraction tension between Planck and DESI measurements, alleviating related cosmological tensions.

Contribution

It introduces a nonminimal coupling of dark matter to gravity via quintessence, preferred over 3σ, to reconcile CMB and BAO data without crossing w=-1.

Findings

Nonminimal coupling is preferred over 3σ confidence level.

The model relieves tensions on neutrino mass and growth rate.

Misidentification with w0waCDM can fake crossing behavior.

Abstract

The Planck measurement of the cosmic microwave background (CMB) has established the $\Lambda$-cold-dark-matter ($\Lambda$CDM) model as the concordant model along with other observations. However, recent measurements of baryon acoustic oscillations (BAO) from the Dark Energy Spectroscopic Instrument (DESI) have renewed the matter fraction $\Omega_\mathrm{m}$ tension between Planck-$\Lambda$CDM and DESI-$\Lambda$CDM. Directly reconciling this CMB-BAO tension with a dynamical DE in Chevallier-Polarski-Linder (CPL) parametrization seems to imply a crossing of the equation-of-state (EOS) through $w=-1$ at low redshifts. In this paper, we resolve this $\Omega_\mathrm{m}$ tension by allowing for the DM nonminimally coupled to gravity via a quintessence field. This non-minimal coupling is preferred over $3\sigma$ confidence level. Consequently, even though the usual effective EOS of the coupled quintessence apart from the standard CDM part never crosses but always is above $w=-1$, a misidentification with the $w_0w_a$CDM model would exactly fake such a crossing behavior, and the tensions on neutrino mass and growth rate in the $\Lambda$CDM model are also relieved in our model as a result of the resolved $\Omega_\mathrm{m}$ tension.