Date/Time
Date(s) - 13/03/2024
3:30 pm - 4:30 pm

Location
Physics and Astronomy Department

ABB room 102

Dr. Avery Broderick
Associate Professor, Perimeter Institute
https://perimeterinstitute.ca/people/avery-broderick

Title: Demystifying the Ring(s): Meaning and Paths to Detection

Abstract:

In 2019, the Event Horizon Telescope (EHT) reported the first image of a black hole in which the event horizon appeared as a dark shadow, silhouetted against the surrounding bright plasma. This image is the product of the extreme astrophysics about the black hole, indelibly marked by strong gravitational lensing that results in an infinite sequence of copies of the emission region. For M87*, the subject of the first image, these images appear as a sequence of (nearly complete) rings, the properties of which present a unique test of general relativity in the near-horizon region. I will discuss what, exactly, measurements of these rings reveal (including the implications of the size of the shadow), and how they complement (and compare with) information from the other recently opened window onto black holes — gravitational waves. I will then review how these rings may be detected now with EHT and with future instruments, and the attendant challenges.