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Related papers: Constraining alternatives to the Kerr black hole

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In this paper, the shadows cast by non-rotating and rotating modified gravity black holes are investigated. In addition to the black hole spin parameter $a$ and the inclination angle $\theta$ of observer, another parameter $\alpha$…

General Relativity and Quantum Cosmology · Physics 2019-04-08 Hui-Min Wang , Yu-Meng Xu , Shao-Wen Wei

The nonminimal coupling of the nonzero vacuum expectation value of the self-interacting antisymmetric Kalb-Ramond field with gravity leads to a power-law hairy black hole having a parameter $s$, which encompasses the Reissner$-$Nordstrom…

General Relativity and Quantum Cosmology · Physics 2020-05-13 Rahul Kumar , Sushant G. Ghosh , Anzhong Wang

We review the physical origins for possible visible images of the supermassive black hole M87* in the galaxy M87 and SgrA* in the Milky Way Galaxy. The classical dark black hole shadow of the maximal size is visible in the case of luminous…

High Energy Astrophysical Phenomena · Physics 2021-12-28 V. I. Dokuchaev , N. O. Nazarova

We perform the shadow calculation of the loop quantum gravity motivated regular black hole recently proposed by Ashtekar, Olmedo and Singh (will be termed AOS black hole hereafter). In the process, we also construct the rotating loop…

General Relativity and Quantum Cosmology · Physics 2023-01-24 Saraswati Devi , Abhinove Nagarajan S , Sayan Chakrabarti , Bibhas Ranjan Majhi

In general relativity, the angular radius of the shadow of a black hole is primarily determined by its mass-to-distance ratio and depends only weakly on its spin and inclination. If general relativity is violated, however, the shadow size…

The black hole shadow, first observed by the Event Horizon Telescope in 2017, is the newest method for studying black holes and understanding gravity. Much work has gone into understanding the shadow of a Kerr black hole, including all of…

General Relativity and Quantum Cosmology · Physics 2022-05-25 Dimitry Ayzenberg

In this Letter, we have developed a numerically efficient framework for evaluating parameters in metric theories of gravity, and applied it to constrain the horizon-scale magnetic field in the Kerr-Bertotti-Robinson (Kerr-BR) spacetime…

General Relativity and Quantum Cosmology · Physics 2026-05-26 Wentao Liu , Yang Liu , Di Wu , Yu-Xiao Liu

The EHT observation revealed event horizon-scale images of the supermassive black holes Sgr A* and M87* and these results are consistent with the shadow of a Kerr black hole as predicted by general relativity. However, Kerr-like rotating…

General Relativity and Quantum Cosmology · Physics 2024-10-10 Shafqat Ul Islam , Sushant G. Ghosh , Sunil D. Maharaj

In this paper, the shadow casted by the rotating black hole inspired by noncommutative geometry is investigated. In addition to the dimensionless spin parameter $a/M_{0}$ with $M_{0}$ black hole mass and inclination angle $i$, the…

General Relativity and Quantum Cosmology · Physics 2015-08-18 Shao-Wen Wei , Peng Cheng , Yi Zhong , Xiang-Nan Zhou

The Event Horizon Telescope (EHT) has imaged the shadow of the supermassive black hole in M87. A library of general relativistic magnetohydrodynamics (GMRHD) models was fit to the observational data, providing constraints on black hole…

High Energy Astrophysical Phenomena · Physics 2021-06-09 Freek Roelofs , Christian M. Fromm , Yosuke Mizuno , Jordy Davelaar , Michael Janssen , Ziri Younsi , Luciano Rezzolla , Heino Falcke

Recently, new exploratory channels have opened up for the physics of highly compact objects, such as gravitational waves and black hole shadows. Moreover, more precise analysis and observations are now possible in the physics of accretion…

General Relativity and Quantum Cosmology · Physics 2024-10-01 D. Pugliese , H. Quevedo

We investigate a rotating black hole embedded in a five-dimensional flat bulk by extending the Kerr metric through the Gurses-Gursey line element. Employing Boyer-Lindquist coordinates, we reinterpret the black hole as a charged-like object…

General Relativity and Quantum Cosmology · Physics 2025-10-10 Abraao J. S. Capistrano , Antonio C. Gutierrez-Pineres , Carlos H. Coimbra-Araujo

In this article, we present the thermodynamic and shadow properties of rotating black holes with global monopole charge. The angular diameter of Sgr A$^{*}$ black hole is 48.7 $\pm$ 7 $\mu as$, which is 8 $kps$ far away having a mass of $M…

General Relativity and Quantum Cosmology · Physics 2025-06-04 Balendra Pratap Singh , Md Sabir Ali

We study the shadows cast by near-extremal Kerr-MOG black holes for different values of the parameter in modified gravity (MOG). In particular, we consider an isotropic emitter orbiting near such black holes and analytically compute the…

General Relativity and Quantum Cosmology · Physics 2018-11-12 Minyong Guo , Niels A. Obers , Haopeng Yan

We examine the shadow cast by a Kerr black hole, focusing on constraints on photons corresponding to different shadow boundaries. The photons are related to different orbital ranges and impact parameter values, creating a map of the shadow…

General Relativity and Quantum Cosmology · Physics 2024-05-24 D. Pugliese , Z. Stuchlık

The recent Event Horizon Telescope (EHT) observations of the M87* have led to a surge of interest in studying the shadow of black holes. Besides, investigation of time evolution and lifetime of black holes helps us to veto/restrict some…

General Relativity and Quantum Cosmology · Physics 2023-02-14 S. H. Hendi , Kh. Jafarzade , B. Eslam Panah

The study of black hole (BH) shadows provide crucial insights into the nature of strong gravitational effects and the intricate structure of the spacetime surrounding BHs. In this paper, we explore the shadow of Kerr MOG BH within a plasma…

General Relativity and Quantum Cosmology · Physics 2025-04-30 Saira Yasmin , Khadije Jafarzade , Mubasher Jamil

The recently released images of the supermassive black holes in the M87 galaxy and the galaxy of our own make probing black hole spacetimes and testing general relativity (GR) possible. The violation of equatorial reflection symmetry of…

General Relativity and Quantum Cosmology · Physics 2022-08-04 Che-Yu Chen

Real astronomical objects possess spin, yet deriving exact solutions for rotating black holes within gravitational theories is a formidable challenge. To understand the shadow of rotating black holes in Lorentz-violating spacetimes induced…

General Relativity and Quantum Cosmology · Physics 2025-08-04 Wentao Liu , Di Wu , Jieci Wang

We establish a thermodynamic-optical duality that directly bridges the semiclassical quantum evaporation of black holes with their classical macroscopic geometry. By employing a diffeomorphic inversion, we re-parameterize the intrinsic…

General Relativity and Quantum Cosmology · Physics 2026-04-27 Nikko John Leo S. Lobos , Emmanuel T. Rodulfo