Supermassive primordial black holes from inflation

Aurora Ireland
Fri February 9th 2024, 3:00 - 4:30pm
University of Chicago
Varian 312

Much remains to be understood about the origin and evolution of our universe's largest supermassive black holes (SMBHs). In this talk, I motivate the possibility that some fraction of these SMBHs may be primordial in origin, having formed from the direct collapse of density perturbations seeded by inflation. Such a scenario is naively in conflict with constraints from CMB spectral distortions, but can be made viable for a distribution of curvature perturbations which is highly non-Gaussian. After quantifying the departure from Gaussianity needed to evade these bounds, I explore a model of multi-field inflation which has all the necessary ingredients to yield such dramatic non-Gaussianities. This scenario has a number of interesting implications and is especially timely in light of recent observations of high-redshift massive galaxy candidates by JWST as well as evidence from the NANOGrav collaboration and other pulsar timing arrays for a stochastic gravitational wave background consistent with SMBH mergers.