Constraints on black-hole charges with the 2017 EHT observations of M87*
Prashant Kocherlakota, Luciano Rezzolla, H. Falcke, Christian M. Fromm, M. Krämer, Yosuke Mizuno, Antonios Nathanail, Héctor Olivares, Ziri Younsi, Kazunori Akiyama, Antxon Alberdi, W. Alef, Juan Carlos Algaba, Richard Anantua, Keiichi Asada, Rebecca Azulay, Anne-Kathrin Baczko, David Ball, Mislav Baloković, John Barrett, B. A. Benson, Dan Bintley, Lindy Blackburn, R. Blundell, W. Boland, Katherine L. Bouman, Geoffrey C. Bower, Hope Boyce, Michael Bremer, Christiaan D. Brinkerink, Roger Brissenden, S. Britzen, Avery E. Broderick, Dominique Broguière, Thomas Bronzwaer, Do‐Young Byun, J. E. Carlstrom, Andrew Chael, Chi‐kwan Chan, Shami Chatterjee, Koushik Chatterjee, Ming‐Tang Chen, Xiaopeng Cheng, Paul M. Chesler, Ilje Cho, Pierre Christian, J. E. Conway, J. M. Cordes, T. M. Crawford, G. Crew, Alejandro Cruz-Osorio, Yuzhu Cui, Jordy Davelaar, Mariafelicia De Laurentis, Roger Deane, Jessica Dempsey, G. Desvignes, Sheperd S. Doeleman, Ralph P. Eatough, Joseph Farah, Vincent L. Fish, Ed Fomalont, Raquel Fraga-Encinas, Per Friberg, H. Alyson Ford, Antonio Fuentes, Peter Galison, Charles F. Gammie, Roberto García, Olivier Gentaz, Boris Georgiev, C. Goddi, Roman Gold, José L. Gómez, Arturo I. Gómez-Ruiz, Minfeng Gu, Mark Gurwell, Kazuhiro Hada, Daryl Haggard, M. H. Hecht, Ronald Hesper, Luis C. Ho, Paul T. P. Ho, Mareki Honma, Chih-Wei L. Huang, Lei Huang, D. H. Hughes, Shiro Ikeda, Makoto Inoue, Sara Issaoun, David J. James, Buell T. Jannuzi, Michaël Janssen, Britton Jeter, Wu Jiang, Alejandra Jiménez-Rosales, Michael D. Johnson, Svetlana G. Jorstad, Taehyun Jung, Mansour Karami
Abstract
Our understanding of strong gravity near supermassive compact objects has recently improved thanks to the measurements made by the Event Horizon Telescope (EHT). We use here the M87* shadow size to infer constraints on the physical charges of a large variety of nonrotating or rotating black holes. For example, we show that the quality of the measurements is already sufficient to rule out that M87* is a highly charged dilaton black hole. Similarly, when considering black holes with two physical and independent charges, we are able to exclude considerable regions of the space of parameters for the doubly-charged dilaton and the Sen black holes.