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Related papers: Black hole shadow to probe modified gravity

200 papers

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

Using the general parametrization of spherically symmetric and asymptotically flat black holes in arbitrary metric theories of gravity and implying that: a) the post-Newtonian constraints are taken into account and b) basic astrophysically…

General Relativity and Quantum Cosmology · Physics 2023-08-10 R. A. Konoplya , A. Zhidenko

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

First sketch of black hole from M87 galaxy was obtained by Event Horizon Telescope, recently. As appearance of black hole shadow reflects space-time geometry of black holes, observations of black hole shadow may be a promising way to test…

General Relativity and Quantum Cosmology · Physics 2020-06-30 Zhe Chang , Qing-Hua Zhu

One of the most important and actual issues in relativistic astrophysics is testing gravity theories and obtaining constraint values for the parameters of black holes using observational data. In this research, we aimed to explore the…

General Relativity and Quantum Cosmology · Physics 2024-06-14 Saeed Ullah Khan , Javlon Rayimbaev , Furkat Sarikulov , Ozodbek Abdurakhmonov

In this paper, we study the influence of the parameters for the accelerating Kerr-Newman black hole on the shadows and the constraints, extensively. We find that the rotating parameter $a$, the charge parameter $e$, and the inclination…

General Relativity and Quantum Cosmology · Physics 2023-11-21 Tao-Tao Sui , Qi-Ming Fu , Wen-Di Guo

In this paper, we use a suitable conformal rescaling to construct static and rotating regular black holes in conformal massive gravity. The new metric is characterized by the mass $M$, the "scalar charge" $Q$, the angular momentum parameter…

General Relativity and Quantum Cosmology · Physics 2020-02-18 Kimet Jusufi , Mubasher Jamil , Hrishikesh Chakrabarty , Qiang Wu , Cosimo Bambi , Anzhong Wang

We study the shadow cast by rotating black holes surrounded by plasma in the context of the 4D Einstein-Gauss-Bonnet theory of gravity. The metric for these black holes results from applying the Newman-Janis algorithm to a spherically…

General Relativity and Quantum Cosmology · Physics 2023-01-30 Javier Badía , Ernesto F. Eiroa

In this paper,we discuss optical properties of the nonlinear magnetic charged black hole surrounded by quintessence with a non-zero cosmological constant $\Lambda$. Setting the state parameter $\omega=-3/2$ , we studied the horizon, the…

General Relativity and Quantum Cosmology · Physics 2021-04-26 Yuan Chen , He-Xu Zhang , Tian-Chi Ma , Jian-Bo Deng

We consider a simple model of a black hole surrounded by a toroidal structure and experiencing deformation due to magnetic field and the tidal force. For this system we construct the shadows of Preston-Poisson black hole, apply it to…

General Relativity and Quantum Cosmology · Physics 2020-08-14 R. A. Konoplya , Jan Schee , Dmitriy Ovchinnikov

A brief illustrative discussion of the shadows of black holes at local and cosmological distances is presented. Starting from definition of the term and discussion of recent observations, we then investigate shadows at large, cosmological…

General Relativity and Quantum Cosmology · Physics 2019-10-24 G. S. Bisnovatyi-Kogan , O. Yu. Tsupko , V. Perlick

We set out to bridge the gap between regular black-hole spacetimes and observations of a black-hole shadow by the Event Horizon Telescope. We explore modifications of spinning and non-spinning black-hole spacetimes inspired by…

General Relativity and Quantum Cosmology · Physics 2019-06-19 Aaron Held , Roman Gold , Astrid Eichhorn

This research delves into the optical characteristics of stationary, spherically symmetric black holes. These black holes follow the Konoplya-Zhidenko deformation rule in arbitrary gravity theories. This research finds that the effects of…

General Relativity and Quantum Cosmology · Physics 2025-05-28 Qiao Yue , Zhaoyi Xu , Meirong Tang

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 co-varying physical couplings (CPC) framework states that physical parameters like the speed of light in vacuum $c$, the Newtonian constant $G$, and the cosmological constant $\Lambda$ could indeed vary with the spacetime coordinates…

General Relativity and Quantum Cosmology · Physics 2023-10-18 R. R. Cuzinatto , C. A. M. de Melo , Juliano C. S. Neves

We calculate the characteristics of the "black hole shadow" for a rotating, neutral black hole in fourth-order conformal Weyl gravity. It is shown that the morphology is not significantly affected by the underlying framework, except for…

General Relativity and Quantum Cosmology · Physics 2018-04-13 Jonas R. Mureika , Gabriele U. Varieschi

When the the shadow image of a supermassive black hole in the center of M87 was obtained a new era in the observational astrophysics began. The resolution improvement would allow to test extended gravity models at event horizon scales. We…

General Relativity and Quantum Cosmology · Physics 2020-08-26 S. O. Alexeyev , V. A. Prokopov

Black hole shadows are a widespread topic in astrophysics. This paper searches for an optical view of the black hole and the relationship between black hole shadow and photon sphere with curvature. We were inspired by the observations of…

General Relativity and Quantum Cosmology · Physics 2025-08-26 Ajay Kumar Sharma , Kanav Ganguly , Murli Manohar Verma

We employ Bozza's method to calculate the deflection angle of light in the presence of the strong gravitational field generated by an improved Schwarzschild-like black hole whose metric, regular throughout the entire spacetime, was derived…

General Relativity and Quantum Cosmology · Physics 2025-10-22 Javier Chagoya , I. Díaz-Saldaña , Benito Rodríguez , Wilfredo Yunpanqui

In this work, we observe that in the presence of the string cloud parameter $a$ and the quintessence parameter $\gamma$, with the equation of state parameter $\omega_q={-2}/{3}$ the radius of the shadow of the Schwarzschild black hole…

General Relativity and Quantum Cosmology · Physics 2022-12-01 Ghulam Mustafa , Farruh Atamurotov , Ibrar Hussain , Sanjar Shaymatov , Ali Övgün