Solving both $H_0$ and $\sigma_8$ tensions in $f(T)$ gravity

TL;DR

This paper demonstrates that a specific $f(T)$ gravity model can simultaneously resolve the $H_0$ and $\sigma_8$ tensions, providing a novel approach to modified gravity as an alternative to standard cosmology.

Contribution

The study introduces a new $f(T)$ gravity parametrization that can fit cosmological observations and alleviate two major tensions simultaneously, a first in the field.

Findings

The $f(T)$ model fits observational data effectively.

It alleviates both $H_0$ and $\sigma_8$ tensions.

This supports modified gravity as a viable alternative.

Abstract

We report how to alleviate both the $H_0$ and $\sigma_8$ tensions simultaneously within $f(T)$ gravity. In particular, we consider the parametrization $f(T)=-T-2\Lambda/M_P^2+\alpha T^\beta$, where two out of the three parameters are independent. This model can efficiently fit observations solving the two tensions. To our knowledge, this is the first time where a modified gravity theory can alleviate both $H_0$ and $\sigma_8$ tensions simultaneously, hence, offering an additional argument in favor of gravitational modification.