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arXiv · 2302.10246

On the Tremaine-Gunn Limit with Mass-Varying Particles

Lotfi Boubekeur·Stefano Profumo
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Abstract

General classical arguments on the time evolution of the phase-space density can be used to derive constraints on the mass of particle candidates for the cosmological dark matter (DM). The resulting Tremaine-Gunn limit is extremely useful in constraining particle DM models. In certain models, however, the DM particle mass varies appreciably over time. In this work, we generalize the phase-space limits on possible DM particle masses to these scenarios. We then examine the ensuing cosmological implications on the effective DM equation of state and indirect DM detection.

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Lotfi Boubekeur, Stefano Profumo. 2023-02-20. On the Tremaine-Gunn Limit with Mass-Varying Particles. https://doi.org/10.1103/physrevd.107.103535

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