Physics Colloquium

A decade of black hole observations with gravitational waves

In just ten years, gravitational-wave astrophysics has progressed from a young, promising field to one with an observational yield of hundreds of signals. Spearheaded by the twin LIGO detectors, the most sensitive detectors to date, observations of merging black holes have revealed a diverse population of stellar-mass objects. These discoveries have reshaped our understanding of black hole demographics and have enabled unprecedented tests of gravity in the strong-field, highly dynamical regime. In this talk, I will review key results on black holes obtained from hundreds of gravitational-wave detections. I will also discuss GW250114, the "decadal" signal of gravitational-wave astronomy that showcases the promise of the upgraded LIGO detectors for probing the fundamental nature of black holes and gravity. GW250114's exceptionally high signal-to-noise ratio enabled the direct observation of multiple quasinormal modes in the ringdown of the remnant black hole. This landmark measurement allowed us to test the no-hair theorem, which links the mode frequencies to the Kerr spectrum, as well as Hawking's black hole area law, which states that the total horizon area of black holes cannot decrease.

Join via Zoom:
https://caltech.zoom.us/j/84497014003
Meeting ID: 844 9701 4003

The colloquium is held in Feynman Lecture Hall, 201 E. Bridge.