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arXiv · 2301.06881

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

Emmanuel N. Saridakis
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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.

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Emmanuel N. Saridakis. 2023-01-17. Solving both $H_0$ and $\sigma_8$ tensions in $f(T)$ gravity. https://arxiv.org/abs/2301.06881

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