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arXiv · 1801.09415

Primordial Black Holes from Inflation and non-Gaussianity

G. Franciolini·A. Kehagias·S. Matarrese·A. Riotto
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Abstract

Primordial black holes may owe their origin to the small-scale enhancement of the comoving curvature perturbation generated during inflation. Their mass fraction at formation is markedly sensitive to possible non-Gaussianities in such large, but rare fluctuations. We discuss a path-integral formulation which provides the exact mass fraction of primordial black holes at formation in the presence of non-Gaussianity. Through a couple of classes of models, one based on single-field inflation and the other on spectator fields, we show that restricting to a Gaussian statistics may lead to severe inaccuracies in the estimate of the mass fraction as well as on the clustering properties of the primordial black holes.

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G. Franciolini, A. Kehagias, S. Matarrese, A. Riotto. 2018-01-29. Primordial Black Holes from Inflation and non-Gaussianity. https://doi.org/10.1088/1475-7516%2F2018%2F03%2F016

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