English

Resolving the Planck-DESI tension by nonminimally coupled quintessence

Cosmology and Nongalactic Astrophysics 2026-04-29 v5 High Energy Physics - Phenomenology

Abstract

The Planck measurement of the cosmic microwave background (CMB) has established the Λ\Lambda-cold-dark-matter (Λ\LambdaCDM) 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 Ωm\Omega_\mathrm{m} tension between Planck-Λ\LambdaCDM and DESI-Λ\LambdaCDM. 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=1w=-1 at low redshifts. In this paper, we resolve this Ωm\Omega_\mathrm{m} tension by allowing for the DM nonminimally coupled to gravity via a quintessence field. This non-minimal coupling is preferred over 3σ3\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=1w=-1, a misidentification with the w0waw_0w_aCDM model would exactly fake such a crossing behavior, and the tensions on neutrino mass and growth rate in the Λ\LambdaCDM model are also relieved in our model as a result of the resolved Ωm\Omega_\mathrm{m} tension.

Keywords

Cite

@article{arxiv.2508.01759,
  title  = {Resolving the Planck-DESI tension by nonminimally coupled quintessence},
  author = {Jia-Qi Wang and Rong-Gen Cai and Zong-Kuan Guo and Shao-Jiang Wang},
  journal= {arXiv preprint arXiv:2508.01759},
  year   = {2026}
}

Comments

v4, 16 pages, 9 figures, 3 tables, version accepted for publication in Physical Review D; v5, to match the published version