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Department of Physics and Astronomy
University of Mississippi

Events

Event Information:

  • Tue
    02
    Nov
    2021

    Colloquium: The Black Hole Photon Ring

    4:00 pmLewis Hall 101

    Alexandru Lupsasca
    Department of Physics
    Princeton

    The Black Hole Photon Ring

    The photon ring is a narrow ring-shaped feature, predicted by General Relativity but not yet observed, that appears on images of sources near a black hole. It is caused by extreme bending of light within a few Schwarzschild radii of the event horizon and provides a direct probe of the unstable bound photon orbits of the Kerr geometry. I will review the origin and structure of the photon ring, before discussing the prospects for its future detection. I will argue that the precise shape of the observable photon ring is remarkably insensitive to the astronomical source profile and can therefore be used as a stringent test of strong-field General Relativity. A space-based interferometry experiment targeting the photon ring of M87* could test the Kerr nature of the source to the sub-sub-percent level.

     

    Join Zoom Meeting

    https://olemiss.zoom.us/j/91928227187

    Meeting ID: 919 282 27187