Speaker: Angelo Ricarte (Harvard University)

Abstract: The past few years have featured major advances in supermassive black hole astrophysics: from the gravitational wave background, to measurements at cosmic dawn, to the first spatially resolved images.  These observations, in tandem with theoretical advances on both event horizon and galactic scales, have spurred progress on longstanding problems in black hole seeding, accretion, feedback, and dynamics.  I will first explain how we image black holes with the Event Horizon Telescope, a worldwide network of millimeter observatories, and how these images favor models with saturated magnetic fields.  I will then introduce Serotina, a flexible semi-analytic modeling framework for the black hole-galaxy co-evolution on cosmological timescales.  I will use this cosmological framework to self-consistently predict multi-messenger observables including spin distributions, high-redshift luminosity functions, and gravitational waves.  We will explore the cosmological implications of magnetically saturated accretion disks and compute observational signatures in black hole populations.  As new types of observations become available in the next decade, this multi-scale theoretical approach will enable us to construct a holistic picture of supermassive black hole evolution over cosmic time.