Redshift-space distortion constraints on the neutrino mass and models to alleviate the Hubble tension

TL;DR

This paper investigates how redshift-space distortion data influence constraints on neutrino mass and dark energy models, finding that certain extended models can better address the Hubble tension and other cosmological discrepancies.

Contribution

It evaluates the impact of RSD observations on neutrino mass limits and extended cosmological models, proposing a varying electron mass model as a promising solution to multiple tensions.

Findings

RSD data lead to a smaller amplitude of perturbations.

Including RSD weakens the upper limit on neutrino mass.

The varying electron mass model can simultaneously relax Hubble and $S_8$ tensions.

Abstract

We discuss the neutrino mass and Hubble tension solutions and examine their effects on the redshift-space distortion (RSD) observations. An analysis with RSD data indicates smaller amplitude of perturbation. Including RSD data results in a slightly weaker upper limit on the neutrino mass than that derived for data without RSD, which is common in other extended models too. We have evaluated the impacts of RSD observations on some extended models, including the varying electron mass model, a time-dependent dark energy model with two parameter equations of state (EOS), and a model where the number of neutrino species is free. When we estimate the cosmological parameters for data including RSD, we found that the EOS parameter for dark energy is larger than that of the cosmological constant, and the effective number of neutrino species is smaller than the standard value, which infers a smaller present Hubble parameter $H_0$. From the viewpoint of cosmological tensions, the varying electron mass model with nonzero neutrino mass option looks promising to relax the Hubble tension and the $S_8$ tension simultaneously.