Resolving the Planck-DESI tension by non-minimally coupled quintessence

Resolving the Planck-DESI tension by non-minimally coupled quintessence
Jia-Qi Wang, Rong-Gen Cai, Zong-Kuan Guo, Shao-Jiang Wang
arXiv:2508.01759v4 Announce Type: replace
Abstract: The Planck measurement of 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 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 letter, we resolve this $Omega_mathrm{m}$ tension by allowing for the DM non-minimally coupled to gravity via a quintessence field. This non-minimal coupling is preferred over $3sigma$ confidence level. Consequently, even though the usual effective EoS of the coupled quintessence apart from the standard CDM part never crosses but always 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.arXiv:2508.01759v4 Announce Type: replace
Abstract: The Planck measurement of 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 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 letter, we resolve this $Omega_mathrm{m}$ tension by allowing for the DM non-minimally coupled to gravity via a quintessence field. This non-minimal coupling is preferred over $3sigma$ confidence level. Consequently, even though the usual effective EoS of the coupled quintessence apart from the standard CDM part never crosses but always 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.