Conceptual

Primordial Black Hole Abundance from a Finite-Width Power Spectrum via Peaks Theory

A general, systematic peaks-theory method computes the abundance of primordial black holes formed from a broad (finite-width) power spectrum of Gaussian curvature perturbations. A window function selects the perturbation scales relevant to PBHs of a given mass and a filter function removes unphysical contributions from super-horizon-scale overdensities; applied to a log-normal spectrum (with monochromatic and high-peak limits) the method substantially reduces the long-standing discrepancy between the density-peaks calculation and the Press-Schechter estimate of the PBH mass function, with residual uncertainty from the nonlinear collapse threshold.