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arXiv · 2211.08348

Non-perturbative non-Gaussianity and primordial black holes

Andrew D. Gow·Hooshyar Assadullahi·Joseph H. P. Jackson·Kazuya Koyama·Vincent Vennin·David Wands
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Abstract

We present a non-perturbative method for calculating the abundance of primordial black holes given an arbitrary one-point probability distribution function for the primordial curvature perturbation, $P(\zeta)$. A non-perturbative method is essential when considering non-Gaussianities that cannot be treated using a conventional perturbative expansion. To determine the full statistics of the density field, we relate $\zeta$ to a Gaussian field by equating the cumulative distribution functions. We consider two examples: a specific local-type non-Gaussian distribution arising from ultra slow roll models, and a general piecewise model for $P(\zeta)$ with an exponential tail. We demonstrate that the enhancement of primordial black hole formation is due to the intermediate regime, rather than the far tail. We also show that non-Gaussianity can have a significant impact on the shape of the primordial black hole mass distribution.

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Andrew D. Gow, Hooshyar Assadullahi, Joseph H. P. Jackson, Kazuya Koyama, Vincent Vennin, David Wands. 2022-11-15. Non-perturbative non-Gaussianity and primordial black holes. https://doi.org/10.1209/0295-5075%2Facd417

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