Topic: Perturbations of black holes and stars by generalized vector fields
Speaker: Assist.Prof. Sebastian Garcia-Saenz (South University of Science and Technology of China)
Coordinates: PCFT C1124, 16:00, Thursday, Dec 16
Abstract: I will discuss recent results on the analysis of perturbations of non-minimally coupled vector fields in the background spacetime of a black hole or perfect fluid star. The model is very general, encompassing the whole class of generalized Proca theories in the regime of interest. For localized perturbations, I will describe a destabilization channel affecting black holes with sufficiently small mass and stars with sufficiently high densities. The stability criteria imply interesting bounds of relevance for scenarios of dark energy and ultra-light dark matter, and suggest that solutions with vector hair within these models cannot form through a vectorization mechanism. In the case of a Schwarzschild black hole, I will present further results beyond the short-wavelength approximation, including a calculation of vector quasi-normal modes and susceptibility coefficients.