Cosmological constraints on matter density perturbations amplitude, neutrino mass and number of relativistic species

Space Research Institute of RAS (IKI), Moscow, Russia

^* e-mail: rodion@hea.iki.rssi.ru

Published online: 31 October 2018

Abstract

It is shown that Planck CMB temperature anisotropy data at high multipoles, ℓ > 1000, produce the measurement of matter density perturbations amplitude that contradict to all other constraints obtained both from remaining Planck CMB anisotropy data and from other cosmological data, at about 3:7σ significance level. With the exception of Planck CMB temperature anisotropy data at high multipoles, all other measurements of density perturbation amplitude are in good agreement between each other and give the following measurements of linear density perturbation amplitude: σ₈ = 0:792 ± 0:006, mean density of the Universe: Ω_m = 0:287 ± 0:007, and Hubble constant: H₀ = 69:4 ± 0:6 km s^-1 Mpc^-1. Therefore, in this case the tensions in H₀ constraints between Planck+BAO data and direct H₀ measurements are weaken, and the tensions in σ₈ measurements between Planck CMB data and large scale structure data disappear completely. Taking in account the data on baryon acoustic oscillations and (or) direct measurements of the Hubble constant, one can obtain different constraints on sum of neutrino mass and number of relativistic species.