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arXiv · 2401.09408

Were you born in an aborted primordial black hole?

Emilie Despontin·Sebastien Clesse·Albert Escrivà·Cristian Joana
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Abstract

We propose a mechanism of electroweak baryogenesis based on the Standard Model and explaining the coincidence between the baryon and Dark Matter (DM) densities. Large curvature fluctuations slightly below the threshold for Primordial Black Hole (PBH) formation locally reheat the plasma above the sphaleron barrier when they collapse gravitationally, leading to regions with a maximal baryogenesis at the Quantum Chromodynamics epoch. Using numerical relativity simulations, we calculate the overdensity threshold for baryogenesis. If PBH significantly contribute to the DM, aborted PBHs can generate a baryon density and an averaged baryon-to-photon ratio consistent with observations.

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Emilie Despontin, Sebastien Clesse, Albert Escrivà, Cristian Joana. 2024-01-17. Were you born in an aborted primordial black hole?. https://arxiv.org/abs/2401.09408

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