Title: Gravitational waves and the nature of relativistic compact objects
Speaker: Chris Van Den Broeck (NIKHEF)
Abstract: The direct detection of gravitational waves from (presumed) binary black hole mergers, and more recently a binary neutron star coalescence, has enabled unprecedented access to the strong-field dynamics of spacetime, and given us ways to study how gravitational waves propagate over large distances, which I will briefly review. A natural next step is to empirically probe the nature of the compact objects themselves. In recent years a number of alternative objects to the "standard" black holes of classical general relativity have been proposed, which tend to have the property that they violate the black hole no-hair conjecture, or cause so-called gravitational wave echoes, or both. Concrete data analysis methods are under development to study these effects. As I will show, with expected upgrades of the Advanced LIGO and Virgo detectors over the next few years, the no-hair conjecture will be tested with an accuracy of a few percent. Similarly, if echoes exist then depending on their properties they will become detectable with great confidence; alternatively, stringent constraints will be placed.