Perturbations of rapidly rotating relativistic stars

We examine the perturbations of rapidly rotating relativistic stars. We first summarize the properties of rapidly rotating relativistic stars in equilibrium. Then, we define small (linear) perturbations and impose them upon the unperturbed equilibrium state. By perturbing, also, the local law of energy-momentum conservation, we derive a system of partial differential equations (PDEs) for the time evolution of these perturbations. We then evolve this system forward in time numerically and, by a fast Fourier transform, we obtain its characteristic eigenfrequencies. (author)