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arXiv · 2105.10803

Growth of structures and redshift-space distortion data in scale-dependent gravity

Grigoris Panotopoulos·Ángel Rincón
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Abstract

This study is devoted to the implications of scale-dependent gravity in Cosmology. Redshift-space distortion data indicate that there is a tension between $\Lambda$CDM and available observations as far as the value of the rms density fluctuation, $\sigma_8$, is concerned. It has been pointed out that this tension may be alleviated in alternative theories in which gravity is weaker at red-shift $z \sim 1$. We study the evolution of density perturbations for non-relativistic matter on top of a spatially flat FLRW Universe, and we compute the combination $A=f \sigma_8$ in the framework of scale-dependent gravity, where both Newton's constant and the cosmological constant are allowed to vary with time. Upon comparison between available observational data (supernovae data as well as redshift-space distortion data) and theoretical predictions of the model, we determine the numerical value of $\sigma_8$ that best fits the data.

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BibTeXRIS

Grigoris Panotopoulos, Ángel Rincón. 2021-05-22. Growth of structures and redshift-space distortion data in scale-dependent gravity. https://doi.org/10.1140/epjp%2Fs13360-021-01583-w

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