June 30, 2023 8-10PM

Event Type: Lecture and Stargazing
Title: Merging Supermassive Black Holes
Lecturer: Aaron Johnson
Position: Postdoctoral Fellow
Institution: Caltech
Abstract:
Supermassive black holes lurk at the centers of most galaxies. When galaxies merge, their black holes are also predicted to merge, releasing vibrations in the surrounding spacetime known as gravitational waves. While we cannot directly see these gravitational waves, it may be possible to detect them by looking for irregularities in the clock-like flashes coming from distant rotating dead stars known as pulsars. By monitoring a large enough network of pulsars spread around our galaxy for these irregularities, astronomers may find the signs of merging supermassive black holes throughout the universe. Are the merging black holes really out there, and when will we find them? Join us to learn about these so-called "pulsar timing arrays" and whether we can use them to detect and study merging supermassive black holes across the universe.