Dartmouth Events

Physics & Astronomy Colloquium - Dr. Alex Lupsasca, Vanderbilt University

Title: "The Black Hole Photon Ring"

Friday, February 3, 2023
3:30pm – 4:30pm
Wilder 104 & Zoom
Intended Audience(s): Public
Categories: Arts and Sciences, Lectures & Seminars
Abstract: What does a black hole look like? The first images of the supermassive black hole M87* display a bright ring encircling the event horizon, which appears as a dark patch in its surrounding emission. But Einstein's theory of general relativity predicts that within this image there also lies a thin "photon ring" consisting of multiple mirror images of the main emission. These images arise from photons that orbited around the black hole multiple times, probing the warped space-time geometry just outside its horizon. The photon ring carries an imprint of the strong gravity in this region and encodes fundamental properties of the black hole. A measurement of this predicted (but not yet observed) ring could provide a precise test of general relativity and will be the target of a NASA mission proposed to fly within the next decade.
***Join before the Colloquium at 3:00 pm for discussion with speaker, Dr. Sasha Philippov, in Wilder 103, for coffee and cookies!*** 
Hosted by Rufus Boyack
Please click the link below to join the webinar:
Passcode: Physics
For more information, contact:
Tressena Manning

Events are free and open to the public unless otherwise noted.