Quasinormal modes: The characteristic music of black holes - Suneeta Vardarajan

The unique imprint of a black hole can be found in the time behaviour of perturbations of the black hole. Of particular interest is a set of complex frequencies, the quasinormal modes, that describe in part the temporal behaviour of perturbations. Quasinormal modes are interesting because they are characteristic only of the black hole and are not sensitive to the initial conditions of the perturbation. They are in some sense analogous to modes of leaky optical cavities or of musical instruments. In this talk, I describe some of my work and some exciting questions concerning quasinormal modes. I also outline a problem that has generated a lot of excitement : namely, a proposed connection between the area spectrum of a black hole in a quantum theory of gravity and the classical quasinormal mode spectrum.