Raatikainen, Sami and Räsänen, Syksy and Tomberg, Eemeli (2024) Primordial Black Hole Compaction Function from Stochastic Fluctuations in Ultraslow-Roll Inflation. Physical review letters, 133 (12): 121403. ISSN 0031-9007
Full text not available from this repository.Abstract
We study the formation of primordial black holes (PBHs) with ultraslow-roll inflation when stochastic effects are important. We use the ΔN formalism and simplify the stochastic equations with an analytical constant-roll approximation. Considering a viable inflation model, we find the spatial profile of the PBH compaction function numerically for each stochastic patch, without assumptions about Gaussianity or the radial profile. The stochastic effects that lead to an exponential tail for the density distribution also make the compaction function very spiky, unlike as assumed in the literature. Naively using collapse thresholds found for smooth profiles, the PBH abundance is enhanced by up to a factor of 109, and the PBH mass distribution is spread over 3 orders of magnitude in mass. The results point to a need to redo numerical simulations of PBH formation with spiky profiles. Published by the American Physical Society 2024