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arXiv · 2211.08359

Dark Matter from freeze-in and its inhomogeneities

Alessandro Strumia
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Abstract

We consider generic freeze-in processes for generation of Dark Matter, together with the consequent re-thermalization of the Standard Model fluid. We find that Dark Matter inherits the Standard Model adiabatic inhomogeneities on the cosmological scales probed by current observations, that were super-horizon during freeze-in. Thereby, freeze-in satisfies the bounds on iso-curvature perturbations.

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Alessandro Strumia. 2022-11-15. Dark Matter from freeze-in and its inhomogeneities. https://doi.org/10.1007/jhep03(2023)042

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