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arXiv · 1908.00900

On the tension between growth rate and CMB data

Alba Quelle·Antonio L. Maroto
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Abstract

We analyze the claimed tension between redshift space distorsions measurements of $f(z)σ_8(z)$ and the predictions of standard $Λ$CDM (Planck 2015 and 2018) cosmology. We consider a dataset consisting of 17 data points extending up to redshift $z=1.52$ and corrected for the Alcock-Paczynski effect. Thus, calculating the evolution of the growth factor in a $w$CDM cosmology, we find that the tension for the best fit parameters $w$, $Ω_m$ and $σ_8$ with respect to the Planck 2018 $Λ$CDM parameters is below $2σ$ in all the marginalized confidence regions.

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Alba Quelle, Antonio L. Maroto. 2020-05-07. On the tension between growth rate and CMB data. https://doi.org/10.1140/epjc%2Fs10052-020-7941-7

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