Astrophysics Seminar

After a decade of groundbreaking black hole and neutron star discoveries, gravitational wave astronomy is now entering an era of precision measurement, opening new observational channels to address fundamental questions about the nature of gravity and matter under extreme conditions. In this talk, I will zoom in on the ringdown phase, the final "ringing" signal emitted when two black holes merge, which provides the cleanest probe of strong-field gravity and the nature of black holes. The recent GW250114 signal enabled the first test of Hawking's area theorem and revealed hints of two distinct ringdown modes, beginning to realize a longstanding ambition of the field. With current detectors already enabling these tests and next-generation instruments promising transformational improvements, ringdown represents a key frontier for testing general relativity with unprecedented precision. 

However, this requires (a) precision theoretical predictions from all possible binary configurations, and (b) reliable parameter inference despite complex detector noise, neither of which are fully developed. A major thrust of my work has been advancing both these fronts to extract robust physics from ringdown signals. In the course of this talk, I will trace how we've progressed from first detections to precision measurements, describe the science enabled by next-generation detectors like Cosmic Explorer and Einstein Telescope, and outline the critical theoretical and analytical developments needed to unlock the full scientific potential of gravitational wave observatories. Bridging these gaps will enable gravitational wave astronomy to fulfill its promise as the premier observatory for testing Einstein's theory in its most extreme regime and revealing the true nature of spacetime.