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arXiv · 2203.09439

Can decaying dark matter scenarios alleviate both $H_0$ and $σ_8$ tensions?

Zahra Davari·Nima Khosravi
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Abstract

Current tensions in cosmology, including $H_0$ and $σ_8$, provide one of the strong reasons to suspect the existence of physics beyond the standard model of cosmology ($Λ$CDM). In this paper, we investigate if there is a relation between these tensions and beyond cold dark matter scenarios. To model non-CDM, we assume a decaying dark matter (DDM) which is unstable and may decay into two daughter particles, a combination of cold dark matter, warm dark matter, and dark radiation, to explore a vast era of possibilities. We checked our model against CMB data and could show that decaying dark matter seems not a promising candidate to address the cosmological tensions.

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Zahra Davari, Nima Khosravi. 2022-03-17. Can decaying dark matter scenarios alleviate both $H_0$ and $σ_8$ tensions?. https://doi.org/10.1093/mnras%2Fstac2306

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