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arXiv · 2406.09122

Primordial black hole formation from self-resonant preheating?

Guillermo Ballesteros·Joaquim Iguaz Juan·Paquale D. Serpico·Marco Taoso
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Abstract

We revisit the question of how generic is the formation of primordial black holes via self-resonant growth of inflaton fluctuations in the post-inflationary, preheating phase. Using analytical and lattice calculations, we find that primordial black hole production is far from being a generic outcome. Also, in most of the parameter space of viable inflationary models, the metric preheating term is subleading to the anharmonic terms and the approximation of a quadratic potential for describing the resonance dynamics is inadequate. Nonetheless, the anharmonicity of the potential cannot be used to rescue the mechanism: The generic outcome of the non-linear evolution of the scalar field in this case is the formation of metastable transients or oscillons, that do not generically collapse into black holes.

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Guillermo Ballesteros, Joaquim Iguaz Juan, Paquale D. Serpico, Marco Taoso. 2024-06-13. Primordial black hole formation from self-resonant preheating?. https://arxiv.org/abs/2406.09122

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