Superdense objects in general relativity : modeling neutron stars with free quark cores

Abstract

We present the results of a numerical study of neutron stars made of a color-flavor locked (CFL) quark matter center and a nuclear fluid exterior. CFL quark matter is a theoretical state of matter which may exist at the center of highly dense neutron stars. To verify its existence, we need to make falsifiable predictions about the differences between typical neutron stars and CFL hybrid neutron stars and verify them observationally. This thesis begins this process by modelling the hybrid neutron stars at rest and while undergoing rotation. We show that Newtonian models are insufficient to correctly describe these objects; their treatment must be relativistic. We also put a bound on the upper rotation speed allowed by our approximations. Finally, we note the presence of the backbending instability in our hybrid star model which may constrain the physically accessible parameters of this model. The tools we have developed in this study are a first step in fully investigating the properties of these objects.