351. Gravitational Test beyond the First Post-Newtonian Order with the Shadow of the M87 Black Hole.
- Author
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Psaltis D, Medeiros L, Christian P, Özel F, Akiyama K, Alberdi A, Alef W, Asada K, Azulay R, Ball D, Baloković M, Barrett J, Bintley D, Blackburn L, Boland W, Bower GC, Bremer M, Brinkerink CD, Brissenden R, Britzen S, Broguiere D, Bronzwaer T, Byun DY, Carlstrom JE, Chael A, Chan CK, Chatterjee S, Chatterjee K, Chen MT, Chen Y, Cho I, Conway JE, Cordes JM, Crew GB, Cui Y, Davelaar J, De Laurentis M, Deane R, Dempsey J, Desvignes G, Dexter J, Eatough RP, Falcke H, Fish VL, Fomalont E, Fraga-Encinas R, Friberg P, Fromm CM, Gammie CF, García R, Gentaz O, Goddi C, Gómez JL, Gu M, Gurwell M, Hada K, Hesper R, Ho LC, Ho P, Honma M, Huang CL, Huang L, Hughes DH, Inoue M, Issaoun S, James DJ, Jannuzi BT, Janssen M, Jiang W, Jimenez-Rosales A, Johnson MD, Jorstad S, Jung T, Karami M, Karuppusamy R, Kawashima T, Keating GK, Kettenis M, Kim JY, Kim J, Kim J, Kino M, Koay JY, Koch PM, Koyama S, Kramer M, Kramer C, Krichbaum TP, Kuo CY, Lauer TR, Lee SS, Li YR, Li Z, Lindqvist M, Lico R, Liu J, Liu K, Liuzzo E, Lo WP, Lobanov AP, Lonsdale C, Lu RS, Mao J, Markoff S, Marrone DP, Marscher AP, Martí-Vidal I, Matsushita S, Mizuno Y, Mizuno I, Moran JM, Moriyama K, Moscibrodzka M, Müller C, Musoke G, Mus Mejías A, Nagai H, Nagar NM, Narayan R, Narayanan G, Natarajan I, Neri R, Noutsos A, Okino H, Olivares H, Oyama T, Palumbo DCM, Park J, Patel N, Pen UL, Piétu V, Plambeck R, PopStefanija A, Prather B, Preciado-López JA, Ramakrishnan V, Rao R, Rawlings MG, Raymond AW, Ripperda B, Roelofs F, Rogers A, Ros E, Rose M, Roshanineshat A, Rottmann H, Roy AL, Ruszczyk C, Ryan BR, Rygl KLJ, Sánchez S, Sánchez-Arguelles D, Sasada M, Savolainen T, Schloerb FP, Schuster KF, Shao L, Shen Z, Small D, Sohn BW, SooHoo J, Tazaki F, Tilanus RPJ, Titus M, Torne P, Trent T, Traianou E, Trippe S, van Bemmel I, van Langevelde HJ, van Rossum DR, Wagner J, Wardle J, Ward-Thompson D, Weintroub J, Wex N, Wharton R, Wielgus M, Wong GN, Wu Q, Yoon D, Young A, Young K, Younsi Z, Yuan F, Yuan YF, and Zhao SS
- Abstract
The 2017 Event Horizon Telescope (EHT) observations of the central source in M87 have led to the first measurement of the size of a black-hole shadow. This observation offers a new and clean gravitational test of the black-hole metric in the strong-field regime. We show analytically that spacetimes that deviate from the Kerr metric but satisfy weak-field tests can lead to large deviations in the predicted black-hole shadows that are inconsistent with even the current EHT measurements. We use numerical calculations of regular, parametric, non-Kerr metrics to identify the common characteristic among these different parametrizations that control the predicted shadow size. We show that the shadow-size measurements place significant constraints on deviation parameters that control the second post-Newtonian and higher orders of each metric and are, therefore, inaccessible to weak-field tests. The new constraints are complementary to those imposed by observations of gravitational waves from stellar-mass sources.
- Published
- 2020
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