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arXiv · 2403.03216

On the (non-)degeneracy of massive neutrinos and elastic interactions in the dark sector

Jose Beltrán Jiménez·David Figueruelo·Florencia Anabella Teppa Pannia
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Abstract

Cosmological models featuring an elastic interaction in the dark sector at linear order has been shown to provide a promising scenario for alleviating the $σ_8$ tension. A natural question for these scenarios is whether there could be a degeneracy between the interaction and massive neutrinos that also contribute to erasing structures at late times. In this work we investigate the presence of such a degeneracy and show that the two effects do not exhibit strong correlations.

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Jose Beltrán Jiménez, David Figueruelo, Florencia Anabella Teppa Pannia. 2024-03-05. On the (non-)degeneracy of massive neutrinos and elastic interactions in the dark sector. https://arxiv.org/abs/2403.03216

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