Exploring $Λ$CDM extensions with SPT-3G and Planck data: 4$σ$ evidence for neutrino masses, full resolution of the Hubble crisis by dark energy with phantom crossing, and all that [CEA]

http://arxiv.org/abs/2203.03666


We present new cosmological constraints in a set of motivated extensions of the $\Lambda$CDM model using the polarization and gravitational lensing measurements from the South Polar Telescope and the Planck CMB temperature observations at large angular scales. It was shown in Ref. \cite{Chudaykin:2020acu} that this CMB setup is free from the Planck anomalies which could affect the cosmological inference in extended models. Combining the SPT-3G, SPTPol and Planck large-scale temperature data with the latest full-shape BOSS and BAO measurements and information from the weak lensing surveys we find a $4\sigma$ evidence for nonzero neutrino mass, $\sum m_\nu=0.23\pm0.06$ eV. In $\rm \Lambda$CDM+$N_{\rm eff}$ scenario we demonstrate that the Planck anomalies do not propagate into cosmological constraints. Then we examine two promising scenarios with modified late-time cosmology: one introduces a phantom crossing in dark energy equation of state, another provides with a sharp transition in the dark energy evolution. We find that the scenario with a phantom crossing completely alleviate the cosmological tensions yielding $H_0=73.93\pm1.08{\rm \,\,km\,s^{-1}Mpc^{-1}}$ and $S_8=0.774\pm0.010$. For the transitional dark energy we find no strong evidence for a rapid change in its equation of state after including the BAO from the BOSS DR12. Our proof-of-concept analysis shows that the Planck anomalies severely obscure the cosmological inference in some extensions of the $\Lambda$CDM model. More precise CMB data is needed to validate our conclusions on neutrino masses and phantom crossing in the dark energy sector.

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A. Chudaykin, D. Gorbunov and N. Nedelko
Wed, 9 Mar 22
28/68

Comments: 39 pages, 10 figures, 6 tables