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Related papers: Shadow casted by a twisted and rotating black hole

200 papers

We examine the shadow of a rotating Kaluza-Klein black hole in Einstein gravity coupled to a Maxwell field and a dilaton. The size and the shape of the shadow depend on the mass, the charge, and the angular momentum of the compact object.…

General Relativity and Quantum Cosmology · Physics 2016-01-14 Leonardo Amarilla , Ernesto F. Eiroa

We consider a simple spherical model consisting of a Schwarzschild black hole of mass $M$ and a dark matter of mass $\Delta M$ around it. The general formula for the radius of black-hole shadow has been derived in this case. It is shown…

General Relativity and Quantum Cosmology · Physics 2019-06-05 R. A. Konoplya

Shadows cast by the rotating black hole in perfect fluid matter are studied using analytical method. We consider three kinds of matter with standard equation of state in Cosmology: $-1/3$ (dark matter), 0 (dust) and $1/3$ (radiation). The…

General Relativity and Quantum Cosmology · Physics 2018-10-31 Zhaoyi Xu , Xian Hou , Jiancheng Wang

The motion of photons around black holes determines the shape of shadow and match the ringdown properties of a perturbed black hole. Observations of shadows and ringdown waveforms will reveal the nature of black holes. In this paper, we…

General Relativity and Quantum Cosmology · Physics 2021-07-29 Song Li , Ahmadjon A. Abdujabbarov , Wen-Biao Han

Due to the gravitational lensing effect, a black hole casts a shadow larger than its horizon over a bright background, and the shape and size can be calculated. The Event Horizon Telescope collaboration has produced the first direct image…

General Relativity and Quantum Cosmology · Physics 2021-09-28 Rahul Kumar , Balendra Pratap Singh , Md Sabir Ali , Sushant G. Ghosh

We investigate the shadow cast by a sort of new regular black holes which are characterized by an asymptotically Minkowski core and the Sub-Planckian curvature. Firstly, we extend the metric with spherical symmetry to the one of rotating…

General Relativity and Quantum Cosmology · Physics 2022-11-17 Yi Ling , Meng-He Wu

Recently a purportedly novel solution of the vacuum Einstein field equations was discovered: it supposedly describes an asymptotically flat twisted black hole in 4-dimensions whose exterior spacetime rotates in a peculiar manner -- the…

General Relativity and Quantum Cosmology · Physics 2017-01-24 Yen Chin Ong

We study analytically the shadow cast by the rotating black hole in the perfect fluid dark matter. The apparent shape of the shadow depends upon the black hole spin $a$ and the perfect fluid dark matter intensity parameter $k$ ($k>0$). In…

General Relativity and Quantum Cosmology · Physics 2018-12-26 Xian Hou , Zhaoyi Xu , Jiancheng Wang

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

It is believed that curvature singularities are a creation of general relativity and hence, in the absence of a quantum gravity, models of nonsingular black holes have received significant attention. We study the shadow (apparent shape), an…

General Relativity and Quantum Cosmology · Physics 2016-08-03 Muhammed Amir , Sushant G. Ghosh

Circular photon orbit and black hole shadow are significantly important issues in physics and astronomy, and a number of breakthroughs have been witnessed in recent years. Conventionally, the stable and unstable circular photon orbits are…

General Relativity and Quantum Cosmology · Physics 2024-09-12 Chen-Kai Qiao , Ming Li

In this paper, we study the shadow produced by rotating black holes with charge in the presence of an anisotropic matter field. We obtain the apparent shape and the corresponding observables characterizing the size, oblateness, and…

General Relativity and Quantum Cosmology · Physics 2020-07-24 Javier Badía , Ernesto F. Eiroa

Recent observations of the supermassive black holes M87* and Sgr A* by the Event Horizon Telescope (EHT) have opened new avenues for testing gravity theories through black hole shadow observables. These observations offer a means to…

General Relativity and Quantum Cosmology · Physics 2025-05-05 Mohsen Fathi , Yassine Sekhmani

Recently there has been a surge of interest in regularizing, a $ D \to 4 $ limit of, the Einstein-Gauss-Bonnet (EGB) gravity, and the resulting regularized $4D$ EGB gravity has nontrivial dynamics. The theory admits spherically symmetric…

General Relativity and Quantum Cosmology · Physics 2020-07-28 Rahul Kumar , Sushant G. Ghosh

We obtain the shadow cast induced by the rotating black hole with an anisotropic matter. A Killing tensor representing the hidden symmetry is derived explicitly. The existence of separability structure implies a complete integrability of…

General Relativity and Quantum Cosmology · Physics 2021-03-24 Bum-Hoon Lee , Wonwoo Lee , Yun Soo Myung

Using a noncommutative inspired Einstein-Euler-Heisenberg black hole, we analyse the associated graviton and light rings that together with the event horizon, provide the necessary components to build its shadow. An analysis of the angular…

General Relativity and Quantum Cosmology · Physics 2021-10-27 Marco Maceda , Alfredo Macías , Daniel Martínez-Carbajal

We have investigated the shadow of a Konoplya-Zhidenko rotating non-Kerr black hole with an extra deformation parameter. The spacetime structure arising from the deformed parameter affects sharply the black hole shadow. With the increase of…

General Relativity and Quantum Cosmology · Physics 2017-11-01 Mingzhi Wang , Songbai Chen , Jiliang Jing

We study the shadow of the rotating black hole with quintessential energy i) in vacuum and ii) in the presence of plasma with radial power-law density. For vacuum case the quintessential field parameter of the rotating black hole…

General Relativity and Quantum Cosmology · Physics 2015-12-18 Ahmadjon Abdujabbarov , Bobir Toshmatov , Zdeněk Stuchlík , Bobomurat Ahmedov

The shadow of a black hole can be one of the strong observational evidences for stationary black holes. If we see shadows at the center of galaxies, we would say whether the observed compact objects are black holes. In this paper, we…

General Relativity and Quantum Cosmology · Physics 2018-03-20 Naoki Tsukamoto

Recently a sequence of inequalities relating the black hole horizon, photon sphere, shadow were proposed for spherically symmetric and static black holes, providing the upper bound for given mass. In this paper, we extend the discussion to…

General Relativity and Quantum Cosmology · Physics 2020-07-15 Xing-Hui Feng , H. Lu