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Related papers: Constraining alternatives to the Kerr black hole

200 papers

We consider a Lorentz violating non-commutating Kerr-like spacetime and studied the superradiance effect and the shadow cast by the back hole. We extensively study the different aspects of the black hole associated with a generalized…

General Relativity and Quantum Cosmology · Physics 2022-04-22 Sohan Kumar Jha , Anisur Rahaman

In this paper we present a new black hole solution surrounded by dark matter halo in the galactic center using the mass model of M87 and that coming from the Universal Rotation Curve (URC) dark matter profile representing family of spiral…

General Physics · Physics 2019-09-04 Kimet Jusufi , Mubasher Jamil , Paolo Salucci , Tao Zhu , Sumarna Haroon

Motivated by the first image of a black hole captured by the Event Horizon Telescope (EHT), there has been a surge of research using observations of black hole shadows to test theories of gravity. In this paper, we carry out a study related…

General Relativity and Quantum Cosmology · Physics 2024-08-06 Qi Sun , Yu Zhang , Chen-Hao Xie , Qi-Quan Li

We investigate Einstein-\AE ther gravity in light of the recent Event Horizon Telescope (EHT) observations of the M87*. The shape and size of the observed black hole shadow contains information of the geometry in its vicinity, and thus one…

General Relativity and Quantum Cosmology · Physics 2021-05-20 Mohsen Khodadi , Emmanuel N. Saridakis

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…

General Relativity and Quantum Cosmology · Physics 2020-10-05 Dimitrios Psaltis , Lia Medeiros , Pierre Christian , Feryal Ozel , Kazunori Akiyama , Antxon Alberdi , Walter Alef , Keiichi Asada , Rebecca Azulay , David Ball , Mislav Balokovic , John Barrett , Dan Bintley , Lindy Blackburn , Wilfred Boland , Geoffrey C. Bower , Michael Bremer , Christiaan D. Brinkerink , Roger Brissenden , Silke Britzen , Dominique Broguiere , Thomas Bronzwaer , Do-Young Byun , John E. Carlstrom , Andrew Chael , Chi-kwan Chan , Shami Chatterjee , Koushik Chatterjee , Ming-Tang Chen , Yongjun Chen , Ilje Cho , John E. Conway , James M. Cordes , Geoffrey B. Crew , Yuzhu Cui , Jordy Davelaar , Mariafelicia De Laurentis , Roger Deane , Jessica Dempsey , Gregory Desvignes , Jason Dexter , Ralph P. Eatough , Heino Falcke , Vincent L. Fish , Ed Fomalont , Raquel Fraga-Encinas , Per Friberg , Christian M. Fromm , Charles F. Gammie , Roberto García , Olivier Gentaz , Ciriaco Goddi , Jose L. Gomez , Minfeng Gu , Mark Gurwell , Kazuhiro Hada , Ronald Hesper , Luis C. Ho , Paul Ho , Mareki Honma , Chih-Wei L. Huang , Lei Huang , David H. Hughes , Makoto Inoue , Sara Issaoun , David J. James , Buell T. Jannuzi , Michael Janssen , Wu Jiang , Alejandra Jimenez-Rosales , Michael D. Johnson , Svetlana Jorstad , Taehyun Jung , Mansour Karami , Ramesh Karuppusamy , Tomohisa Kawashima , Garrett K. Keating , Mark Kettenis , Jae-Young Kim , Junhan Kim , Jongsoo Kim , Motoki Kino , Jun Yi Koay , Patrick M. Koch , Shoko Koyama , Michael Kramer , Carsten Kramer , Thomas P. Krichbaum , Cheng-Yu Kuo , Tod R. Lauer , Sang-Sung Lee , Yan-Rong Li , Zhiyuan Li , Michael Lindqvist , Rocco Lico , Jun Liu , Kuo Liu , Elisabetta Liuzzo , Wen-Ping Lo , Andrei P. Lobanov , Colin Lonsdale , Ru-Sen Lu , Jirong Mao , Sera Markoff , Daniel P. Marrone , Alan P. Marscher , Ivan Martí-Vidal , Satoki Matsushita , Yosuke Mizuno , Izumi Mizuno , James M. Moran , Kotaro Moriyama , Monika Moscibrodzka , Cornelia Muller , Gibwa Musoke , Alejandro Mus Mejías , Hiroshi Nagai , Neil M. Nagar , Ramesh Narayan , Gopal Narayanan , Iniyan Natarajan , Roberto Neri , Aristeidis Noutsos , Hiroki Okino , Hector Olivares , Tomoaki Oyama , Daniel C. M. Palumbo , Jongho Park , Nimesh Patel , Ue-Li Pen , Vincent Pietu , Richard Plambeck , Aleksandar PopStefanija , Ben Prather , Jorge A. Preciado-Lopez , Venkatessh Ramakrishnan , Ramprasad Rao , Mark G. Rawlings , Alexander W. Raymond , Bart Ripperda , Freek Roelofs , Alan Rogers , Eduardo Ros , Mel Rose , Arash Roshanineshat , Helge Rottmann , Alan L. Roy , Chet Ruszczyk , Benjamin R. Ryan , Kazi L. J. Rygl , Salvador Sanchez , David Sanchez-Arguelles , Mahito Sasada , Tuomas Savolainen , F. Peter Schloerb , Karl-Friedrich Schuster , Lijing Shao , Zhiqiang Shen , Des Small , Bong Won Sohn , Jason SooHoo , Fumie Tazaki , Remo P. J. Tilanus , Michael Titus , Pablo Torne , Tyler Trent , Efthalia Traianou , Sascha Trippe , Ilse van Bemmel , Huib Jan van Langevelde , Daniel R. van Rossum , Jan Wagner , John Wardle , Derek Ward-Thompson , Jonathan Weintroub , Norbert Wex , Robert Wharton , Maciek Wielgus , George N. Wong , Qingwen Wu , Doosoo Yoon , Andre Young , Ken Young , Ziri Younsi , Feng Yuan , Ye-Fei Yuan , Shan-Shan Zhao , the EHT Collaboration

The Event Horizon Telescope (EHT) has provided a new tool for testing the strong-field regime of gravity by imaging the shadows of M87* and Sgr A*. These observations provide the first real opportunity to test whether quantum…

General Relativity and Quantum Cosmology · Physics 2026-05-29 Heena Ali , Sushant G. Ghosh

The Event Horizon Telescope (EHT) has recently observed the image and shadow of the supermassive compact object Sagittarius A$^*$ (Sgr A$^*$). According to the EHT collaboration, the observed image is consistent with the expected appearance…

General Relativity and Quantum Cosmology · Physics 2023-05-29 Rajibul Shaikh

Recently, the Event Horizon Telescope (EHT) achieved the realization of an image of the supermassive black hole $\textrm{Sgr~A}^\star$ showing an angular shadow diameter $\mathcal{D}= 48.7 \pm 7\mu as$ and the fractional deviation…

General Relativity and Quantum Cosmology · Physics 2024-04-23 L. Chakhchi , H. El Moumni , K. Masmar

The Event Horizon Telescope has recently provided the first image of the dark shadow around the supermassive black hole M87*. The observation of a highly circular shadow provides strong limits on deviations of M87*'s quadrupole moment from…

General Relativity and Quantum Cosmology · Physics 2020-02-24 Sunny Vagnozzi , Luca Visinelli

In this paper, the structure of a dark matter halo can be well described by the mass model of M87 and the Einasto profile for the cold dark matter model, i.e., $\rho_{\text{eina}} (r)=\rho_\text{e} \exp ( -2 \alpha ^{-1}…

General Relativity and Quantum Cosmology · Physics 2024-02-09 Dong Liu , Yi Yang , Zhaoyi Xu , Zheng-Wen Long

In this work, we investigate the shadow properties of the Kerr-Newman-Anti-de Sitter black hole coupled to a nonlinear electrodynamics. We construct the shadow by employing the celestial coordinate approach for observers located at finite…

General Relativity and Quantum Cosmology · Physics 2025-08-20 Mohsen Fathi

Astrophysical black holes are expected to be described by the Kerr metric. This is the only stationary, vacuum, axisymmetric metric, without electromagnetic charge, that satisfies Einstein's equations and does not have pathologies outside…

High Energy Astrophysical Phenomena · Physics 2023-11-17 The Event Horizon Telescope Collaboration

The Event Horizon Telescope (EHT) observation unveiled the first image of supermassive black hole Sgr A* showing a shadow of diameter $\theta_{sh}= 48.7 \pm 7\,\mu$as with fractional deviation from the Schwarzschild black hole shadow…

General Relativity and Quantum Cosmology · Physics 2022-11-10 Rahul Kumar Walia , Sushant G Ghosh , Sunil D Maharaj

The Event Horizon Telescope has recently observed the images and shadows of the compact objects M87$^*$ and Sgr A$^*$ at the centres of the galaxies Messier 87 and Milky Way. This has opened up a new window in observational astronomy to…

General Relativity and Quantum Cosmology · Physics 2023-05-15 Kunal Pal , Kuntal Pal , Rajibul Shaikh , Tapobrata Sarkar

This paper analyzes the experiment presented in 2019 by the Event Horizon Telescope (EHT) Collaboration that unveiled the first image of the supermassive black hole at the center of galaxy M87. The very first question asked by the EHT…

History and Philosophy of Physics · Physics 2021-03-03 Galina Weinstein

The study of shadows of static and rotating black holes immersed in various dark matter halo profiles has gained significant attention in recent years. In this paper, we consider the static black hole solution immersed in three dark matter…

General Relativity and Quantum Cosmology · Physics 2026-05-19 Malihe Heydari-Fard , Mohaddese Heydari-Fard

The Event Horizon Telescope (EHT) collaboration's image of the compact object at the galactic center is the first direct evidence of the supermassive black hole (BH) Sgr A$^*$. The shadow of Sgr A$^*$ has an angular diameter $d_{sh}= 48.7…

General Relativity and Quantum Cosmology · Physics 2023-02-24 Misba Afrin , Sunny Vagnozzi , Sushant G. Ghosh

We present a method for determining the physical parameters of a Kerr-Newman black hole through shadow observation. In a system comprising a Kerr-Newman black hole, an observer, and a light source, the relevant parameters are mass $M$,…

General Relativity and Quantum Cosmology · Physics 2025-06-17 Kenta Hioki , Umpei Miyamoto

It is often stated in the physics literature that maximally-spinning Kerr black-hole spacetimes are characterized by near-horizon co-rotating circular geodesics of radius $r_{\text{circular}}$ with the property $r_{\text{circular}}\to…

General Relativity and Quantum Cosmology · Physics 2025-02-19 Shahar Hod

With the recent release of the black hole image of Sgr A* alongside the earlier image of M87*, one can achieve an in-depth understanding of gravitational physics at the horizon scale. According to the Event Horizon Telescope (EHT)…

General Relativity and Quantum Cosmology · Physics 2024-05-06 Khadije Jafarzade , Seyed Hossein Hendi , Mubasher Jamil , Sebastian Bahamonde