Monica Colpi (University of Milan)

Title: Massive black holes across cosmic ages

Abstract: Massive black holes (MBHs) inhabit galactic centres, and power luminous quasars and active galactic nuclei, shaping their cosmic environment with the energy they produce. The origins of MBHs remain a mystery, and the recent detection by LIGO/Virgo/KAGRA of a stellar black hole of 142 solar masses has revitalized the questions of whether there is a continuum between ‘stellar’ and ‘massive’ black holes, and what the seeds of MBHs are. Seeds may have formed in the first galaxies or could be related to the collapse of horizon-sized regions in the early Universe. Understanding the origins of MBHs straddles fundamental physics, cosmology and astrophysics, and bridges the fields of gravitational-wave physics and traditional astronomy. With several existing and upcoming facilities in the next 10–15 years, and in particular with LISA and Einstein Telescope, we foresee the possibility of discovering the avenues of formation of MBHs.