Perturbative approach to the quasinormal modes of dirty black holes - art.no. 044034

Using a recently developed perturbation theory for quasinormal modes (QNM's ), we evaluate the shifts in the real and imaginary parts of the QNM freque ncies due to a quasistatic perturbation of the black hole spacetime. We sho w the perturbed QNM spectrum of a black hole can have interesting features using a simple model based on the scalar wave equation. [S0556-2821(99)0770 2-4].