Gravity seminar - Pantelis Pnigouras Seminar

Abstract: As opposed to dynamical instabilities, secular instabilities describe the slow exponential growth of a perturbation, due to the presence of a dissipation mechanism. We will see how they are related to an old problem, regarding the shape of the Earth, and briefly review their manifestation in neutron stars. We will focus on the secular instability driven by the emission of gravitational waves, which can be used to derive information about the largely unknown neutron star interior composition, as well as provide an explanation for some long-standing problems of pulsar observations. Finally, we will present a recently reported study, according to which this instability affects the evolution of neutron star binaries, thus becoming potentially relevant for gravitational-wave detections.