Restoring cosmological concordance with early dark energy and massive neutrinos?

• DOI: 10.3929/ethz-b-000624035
• Publication Date: 2023-01-30
• Authors: Alexander Reeves; Laura Herold; Sunny Vagnozzi; Blake D Sherwin; Elisa G M Ferreira
• Keywords: Cosmology and Nongalactic Astrophysics (astro-ph.CO); cosmic background radiation; large-scale structure of the universe; dark energy; cosmological parameters; cosmology: observations; FOS: Physical sciences; cosmic background radiation; General Relativity and Quantum Cosmology (gr-qc); 01 natural sciences; General Relativity and Quantum Cosmology; cosmic background radiation; cosmological parameters; cosmology: observations; dark energy; large-scale structure of the universe;; High Energy Physics - Phenomenology; High Energy Physics - Phenomenology (hep-ph); 13. Climate action; cosmology: observations; 0103 physical sciences; large-scale structure of the universe; cosmological parameters; dark energy; Astronomy, cartography; info:eu-repo/classification/ddc/520; Astrophysics - Cosmology and Nongalactic Astrophysics

ABSTRACT The early dark energy (EDE) solution to the Hubble tension comes at the cost of an increased clustering amplitude that has been argued to worsen the fit to galaxy clustering data. We explore whether freeing the total neutrino mass Mν, which can suppress small-scale structure growth, improves EDE’s fit to galaxy clustering. Using Planck Cosmic Microwave Background and BOSS galaxy clustering data, a Bayesian analysis shows that freeing Mν does not appreciably increase the inferred EDE fraction fEDE: we find the 95 per cent C.L. upper limits fEDE < 0.092 and $M_{\nu }\lt 0.15\, {\rm eV}$. Similarly, in a frequentist profile likelihood setting (where our results support previous findings that prior volume effects are important), we find that the baseline EDE model (with $M_{\nu }=0.06\, {\rm eV}$) provides the overall best fit. For instance, compared to baseline EDE, a model with $M_\nu =0.24\, {\rm eV}$ maintains the same H0(km/s/Mpc) = (70.08, 70.11, respectively) whilst decreasing S8 = (0.837, 0.826) to the ΛCDM level, but worsening the fit significantly by Δχ2 = 7.5. For the datasets used, these results are driven not by the clustering amplitude, but by background modifications to the late-time expansion rate due to massive neutrinos, which worsen the fit to measurements of the BAO scale.