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arXiv · 1908.04281

Interacting dark energy in the early 2020s: a promising solution to the $H_0$ and cosmic shear tensions

Eleonora Di Valentino·Alessandro Melchiorri·Olga Mena·Sunny Vagnozzi
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Abstract

We examine interactions between dark matter and dark energy in light of the latest cosmological observations, focusing on a specific model with coupling proportional to the dark energy density. Our data includes Cosmic Microwave Background (CMB) measurements from the Planck 2018 legacy data release, late-time measurements of the expansion history from Baryon Acoustic Oscillations (BAO) and Supernovae Type Ia (SNeIa), galaxy clustering and cosmic shear measurements from the Dark Energy Survey Year 1 results, and the 2019 local distance ladder measurement of the Hubble constant $H_0$ from the Hubble Space Telescope. Considering Planck data both in combination with BAO or SNeIa data reduces the $H_0$ tension to a level which could possibly be compatible with a statistical fluctuation. The very same model also significantly reduces the $\Omega_{\rm m}-\sigma_8$ tension between CMB and cosmic shear measurements. Interactions between the dark sectors of our Universe remain therefore a promising joint solution to these persisting cosmological tensions.

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Eleonora Di Valentino, Alessandro Melchiorri, Olga Mena, Sunny Vagnozzi. 2019-08-12. Interacting dark energy in the early 2020s: a promising solution to the $H_0$ and cosmic shear tensions. https://doi.org/10.1016/j.dark.2020.100666

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