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arXiv · 2307.10899

$\Lambda_{\rm s}$CDM model: A promising scenario for alleviation of cosmological tensions

Ozgur Akarsu·Eleonora Di Valentino·Suresh Kumar·Rafael C. Nunes·J. Alberto Vazquez·Anita Yadav
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Abstract

We present a comprehensive analysis of the $\Lambda_{\rm s}$CDM model, which explores the recent conjecture suggesting a rapid transition of the Universe from anti-de Sitter vacua to de Sitter vacua (viz., the cosmological constant switches sign from negative to positive) at redshift ${z_\dagger\sim 2}$, inspired by the graduated dark energy (gDE) model. Our analysis shows that, predicting $z_\dagger\approx1.7$, $\Lambda_{\rm s}$CDM simultaneously addresses the major cosmological tensions of the standard $\Lambda$CDM model, viz., the Hubble constant $H_0$, the Type Ia Supernovae absolute magnitude $M_{\rm B}$, and the growth parameter $S_8$ tensions, along with other less significant tensions such as the BAO Lyman-$\alpha$ discrepancy.

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Ozgur Akarsu, Eleonora Di Valentino, Suresh Kumar, Rafael C. Nunes, J. Alberto Vazquez, Anita Yadav. 2023-07-20. $\Lambda_{\rm s}$CDM model: A promising scenario for alleviation of cosmological tensions. https://arxiv.org/abs/2307.10899

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