The shape of the black hole photon ring: A precise test of strong-field general relativity
AffiliationUniv Arizona, Dept Phys
Univ Arizona, Steward Observ
MetadataShow full item record
PublisherAMER INST PHYSICS
CitationGralla, S. E., Lupsasca, A., & Marrone, D. P. (2020). The shape of the black hole photon ring: A precise test of strong-field general relativity. Physical Review D, 102(12), 124004.
JournalPHYSICAL REVIEW D
Rights© 2020 American Physical Society.
Collection InformationThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at email@example.com.
AbstractWe propose a new test of strong-field general relativity (GR) based on the universal interferometric signature of the black hole photon ring. The photon ring is a narrow ring-shaped feature, predicted by GR 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. We show 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 GR. We forecast that a tailored space-based interferometry experiment targeting M87* could test the Kerr nature of the source to the sub-subpercent level.
VersionFinal published version
SponsorsNational Science Foundation