Supermassive black holes from inflation constrained by dark matter substructure

TL;DR

This paper explores how primordial black holes formed from inflationary density perturbations could seed supermassive black holes, using dark matter substructure observations to constrain the conditions needed for their formation.

Contribution

It provides new bounds on primordial curvature perturbations that could lead to SMBH seeds, linking inflationary models with dark matter substructure data.

Findings

Bounds on curvature perturbations overlap with SMBH seed formation requirements

Constraints apply to Gaussian and non-Gaussian perturbations in a wide mass range

Dark matter substructure observations can probe early universe inflation scenarios

Abstract

Recent James Webb Space Telescope observations of high-redshift massive galaxy candidates have initiated renewed interest in the important mystery around the formation and evolution of our Universe's largest supermassive black holes (SMBHs). We consider the possibility that some of them were seeded by the direct collapse of primordial density perturbations from inflation into primordial black holes and analyze the consequences of this on current dark matter substructures assuming non-Gaussian primordial curvature perturbation distributions. We derive bounds on the enhanced curvature perturbation amplitude from the number of dwarf spheroidal galaxies in our Galaxy, observations of stellar streams and gravitational lensing. We find this bound region significantly overlaps with that required for SMBH seed formation and enables us to probe Gaussian and non-Gaussian curvature perturbations corresponding to the SMBH seeds in the range ${\cal O}(10^5$\text{--}$10^{12}) M_\odot$.