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arXiv · 2409.13807

Evaporating Axion Dark Matter and the Hubble Constant

Daniel Aloni·Hengameh Bagherian·Rashmish K. Mishra
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Abstract

Axion-like particles are a well-motivated dark matter candidate that can form a condensate with low momentum and high occupation number. In the presence of dark radiation, this condensate loses energy, naturally increasing the energy density of the universe around matter-radiation equality without requiring additional inputs. This general mechanism may offer a solution to the Hubble tension.

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Daniel Aloni, Hengameh Bagherian, Rashmish K. Mishra. 2024-09-20. Evaporating Axion Dark Matter and the Hubble Constant. https://arxiv.org/abs/2409.13807

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