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arXiv · 2501.00295

Primordial Black Hole Formation from Power Spectrum with Finite-width

Shi Pi·Misao Sasaki·Volodymyr Takhistov·Jianing Wang
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Abstract

Primordial black holes (PBHs) can form from gravitational collapse of large overdensities in the early Universe, giving rise to rich phenomena in astrophysics and cosmology. We develop a novel, general, and systematic method based on theory of density contrast peaks to calculate the abundance of PBHs for a broad power spectrum of curvature perturbations with Gaussian statistics. We introduce a window function to account for the relevant perturbation scales associated with PBHs of different masses, along with a filter function that removes unphysical contributions from super-horizon-scale overdensities. While some uncertainties remain due to the limited understanding of the nonlinear collapse process, our approach substantially reduces the discrepancy previously observed between peaks theory and the Press-Schechter formalism.

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Shi Pi, Misao Sasaki, Volodymyr Takhistov, Jianing Wang. 2024-12-31. Primordial Black Hole Formation from Power Spectrum with Finite-width. https://doi.org/10.1088/1475-7516/2025/09/045

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