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arXiv · 2004.08111

Primordial Black Holes from Pre-Big Bang inflation

P. Conzinu·M. Gasperini·G. Marozzi
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Abstract

We discuss the possibility of producing a significant fraction of dark matter in the form of primordial black holes in the context of the pre-big bang inflationary scenario. We take into account, to this purpose, the enhancement of curvature perturbations possibly 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, provided the sound-speed parameter is confined in a rather narrow range of values, $0.003 < c_s < 0.01$.

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BibTeXRIS

P. Conzinu, M. Gasperini, G. Marozzi. 2020-04-17. Primordial Black Holes from Pre-Big Bang inflation. https://doi.org/10.1088/1475-7516/2020/08/031

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