Resolving the Planck-DESI tension by nonminimally coupled quintessence

The Planck measurement of the cosmic microwave background (CMB) has established the $Λ$-cold-dark-matter ($Λ$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 $Ω_\mathrm{m}$ tension between Planck-$Λ$CDM and DESI-$Λ$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 $Ω_\mathrm{m}$ tension by allowing for the DM nonminimally coupled to gravity via a quintessence field. This non-minimal coupling is preferred over $3σ$ 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 $Λ$CDM model are also relieved in our model as a result of the resolved $Ω_\mathrm{m}$ tension.