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arXiv · 2404.08318

Non-Gaussianity from primordial black holes

Jinn-Ouk Gong·Naoya Kitajima
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Abstract

We study the effects of non-Gaussianity from primordial black holes (PBHs). The formation of PBHs is in general a rare event and the number of PBHs fluctuates following the Poisson distribution function, which is independent from the pre-existing inflationary adiabatic fluctuations. Such fluctuations can dominate over the adiabatic mode on small scales. We focus on the non-Gaussianity of matter density fluctuations induced by the Poisson fluctuation of PBHs and discuss the potentially observable consequences such as the skewness, kurtosis and the scale-dependent bias.

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Jinn-Ouk Gong, Naoya Kitajima. 2024-04-12. Non-Gaussianity from primordial black holes. https://arxiv.org/abs/2404.08318

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