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arXiv · 2305.01430

Primordial black holes formation in a early matter dominated era from the pre-big bang scenario

Pietro Conzinu·Giovanni Marozzi
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Abstract

We discuss the production of primordial black holes in an early matter dominated era, which typically takes place in string inspired early universe cosmological models. In particular, we consider a pre-big bang scenario (extending previous results regarding formation in the radiation dominated era) where the enhancement of curvature perturbations is induced by a variation of the sound-speed parameter c_s during the string phase of high-curvature inflation. After imposing all relevant observational constraints, we find that the considered class of models is compatible with the production of a large amount of primordial black holes, in the mass range relevant to dark matter, only for a small range of the parameters space. On the other hand, we find that a huge production of light primordial black holes may occur both in such matter dominated era and in the radiation dominated one.

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Pietro Conzinu, Giovanni Marozzi. 2023-05-02. Primordial black holes formation in a early matter dominated era from the pre-big bang scenario. https://arxiv.org/abs/2305.01430

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