Vitor Cardoso was a plenary speaker at the third meeting of the Black Hole Initiative at Harvard. The meeting focused on black hole physics, and included a discussion of the recent Event Horizon Telescope results, as well as the potential science to be studied with VLBI or gravitational-wave data. Vitor summarized the status of our knowledge on the black hole nature of dark, compact and massive objects. Here he is discussing ringdown with Lionel London.
