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arXiv · 1804.07154

Testing Dark energy models in the light of $σ_8$ tension

Gaetano Lambiase·Subhendra Mohanty·Ashish Narang·Priyank Parashari
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Abstract

It has been pointed out that there exists a tension in $σ_8-Ω_m$ measurement between CMB and LSS observation. In this paper we show that $σ_8-Ω_m$ observations can be used to test the dark energy theories. We study two models, (1) Hu-Sawicki(HS) Model of $f(R)$ gravity and (2) Chavallier-Polarski-Linder(CPL) parametrization of dynamical dark energy (DDE), both of which satisfy the constraints from supernovae. We compute $σ_8$ consistent with the parameters of these models. We find that the well known tension in $σ_8$ between Planck CMB and large scale structure (LSS) observations is (1) exacerbated in the HS model and (2) somewhat alleviated in the DDE model. We illustrate the importance of the $σ_8$ measurements for testing modified gravity models. Modified gravity models change the matter power spectrum at cluster scale which also depends upon the neutrino mass. We present the bound on neutrino mass in the HS and DDE model.

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Gaetano Lambiase, Subhendra Mohanty, Ashish Narang, Priyank Parashari. 2018-04-19. Testing Dark energy models in the light of $σ_8$ tension. https://doi.org/10.1140/epjc%2Fs10052-019-6634-6

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