Princeton University LFTP Seminar

Abstract: Black Hole spectroscopy tests the nature of compact objects and General Relativity by measuring the gravitational waves emitted in the last stage of a black hole merger: the ringdown. As detectors improve, we will become sensitive to both nonlinear and nonmodal effects. This demands new theoretical and analysis tools. In this talk, I will review recent developments in black hole perturbation theory at linear order and beyond. I will comment on analytical progress in the low-frequency limit, through scattering amplitudes; in the high-frequency limit, through Penrose limits; and what this all means for ringdown data analysis.