English
Related papers

Related papers: Modified Gravity Black Holes and their Observable …

200 papers

The need for a consistent quantum evolution for black holes has led to proposals that their semiclassical description is modified not just near the singularity, but at horizon or larger scales. If such modifications extend beyond the…

High Energy Astrophysical Phenomena · Physics 2018-04-25 Steven B. Giddings , Dimitrios Psaltis

Recently considered a very attracting possibility to detect retro-MACHOs, i.e. retro-images of the Sun by a Schwarzschild black hole. In this paper we discuss glories (mirages) formed near rapidly rotating Kerr black hole horizons and…

General Relativity and Quantum Cosmology · Physics 2007-05-23 A. F. Zakharov , A. A. Nucita , F. DePaolis , G. Ingrosso

We examine the behavior of non-commutative Schwarzschild black holes in the context of massive gravity. According to the investigation, corresponding to a minimal mass, the black hole can have two horizons, one horizon, or no horizon at…

General Relativity and Quantum Cosmology · Physics 2024-04-17 Piyali Bhar , Dhruba Jyoti Gogoi , Supakchai Ponglertsakul

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

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

Future electromagnetic observations of black holes may allow us to test General Relativity in the strong-field regime. Such tests, however, require knowledge of rotating black hole solutions in modified gravity theories, a class of which…

High Energy Astrophysical Phenomena · Physics 2016-04-25 Dimitry Ayzenberg , Kent Yagi , Nicolas Yunes

With the imaging and characterization of the horizon-scale images of M87* and Sgr A* by the Event Horizon Telescope (EHT), it has become possible to resolve the near-horizon region of astrophysical black holes. As a result, there has been…

High Energy Astrophysical Phenomena · Physics 2023-07-31 Avery E. Broderick , Kiana Salehi , Boris Georgiev

This work explores the shadow of a black hole within the framework of $F(R)$-ModMax gravity coupled with a cloud of strings. The Einstein field equations are solved for a nonlinear ModMax electromagnetic source in the context of $F(R)$…

General Relativity and Quantum Cosmology · Physics 2025-10-28 Ahmad Al-Badawi

We examine the accretion of matter onto a black hole in scalar--tensor--vector gravity (STVG) also known as modified gravity (MOG). The gravitational constant is $G=G_{N} (1 + \alpha)$ where $\alpha$ is a parameter taken to be constant for…

General Relativity and Quantum Cosmology · Physics 2019-11-11 Anslyn J. John

We study the nontrivial effects of the NUT charges on the shadows of the Kerr-Taub-NUT black holes seen by zero-angular-momentum-observers. Inclination angles with which the observers gain maximal, locally extreme or minimal shadow sizes…

General Relativity and Quantum Cosmology · Physics 2021-04-07 Ming Zhang , Jie Jiang

The optical properties of rotating black holes in Kaluza-Klein theory described by the total mass, spin, and electric and magnetic charges are investigated in detail. Using a developed general relativistic ray-tracing code to calculate the…

General Relativity and Quantum Cosmology · Physics 2023-09-12 Temurbek Mirzaev , Askar B. Abdikamalov , Ahmadjon A. Abdujabbarov , Dimitry Ayzenberg , Bobomurat Ahmedov , Cosimo Bambi

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

Regular black hole metrics involve a universal, mass-independent regulator that can be up to O(700) km while remaining consistent with terrestrial tests of Newtonian gravity and astrophysical tests of general relativistic orbits. However,…

General Relativity and Quantum Cosmology · Physics 2024-07-12 Jens Boos , Christopher D. Carone

Black hole shadow and gravitational lensing play important roles in testing gravitational theories in the strong field regime. As the first-order modifications from quantum gravity, the nonlocality can be manifested by black hole shadow and…

General Relativity and Quantum Cosmology · Physics 2022-06-24 Qi-Ming Fu , Shao-Wen Wei , Li Zhao , Yu-Xiao Liu , Xin Zhang

We study the circular motion of massive and massless particles in a recently proposed quantum-corrected Schwarzschild black hole in loop quantum gravity. This solution is supposed to introduce small but non-zero quantum corrections in the…

General Relativity and Quantum Cosmology · Physics 2023-12-20 Reza Saadati , Fatimah Shojai

The recent discovery of the novel four-dimensional static and spherically symmetric Gauss-Bonnet black hole provides a promising bed to test Gauss-Bonnet gravity by using astronomical observations [Phys. Rev. Lett. 124, 081301 (2020)]. In…

General Relativity and Quantum Cosmology · Physics 2024-02-22 Shao-Wen Wei , Yu-Xiao Liu

The presence of dark matter around a black hole remarkably affects its spacetime. We consider the effects of dark matter on the shadow of a new solution to the Einstein equations that describes a rotating black hole in the background of…

General Relativity and Quantum Cosmology · Physics 2019-02-12 Sumarna Haroon , Mubasher Jamil , Kimet Jusufi , Kai Lin , Robert B. Mann

We study the local shadow of the Schwarzschild black hole with a quadrupole distortion and the influence of the external gravitational field on the photon dynamics. The external matter sources modify the light ring structure and lead to the…

General Relativity and Quantum Cosmology · Physics 2018-04-25 Jai Grover , Jutta Kunz , Petya Nedkova , Alexander Wittig , Stoytcho Yazadjiev

We have studied the shadow of a disformal Kerr black hole with an extra deformation parameter, which belongs to non-stealth rotating solutions in quadratic Degenerate Higher Order Scalar Tensor (DHOST) theory. Our result show that the size…

General Relativity and Quantum Cosmology · Physics 2020-12-29 Fen Long , Songbai Chen , Mingzhi Wang , Jiliang Jing

Four spherically symmetric but non-asymptotically flat black hole solutions surrounded with spherical dark matter distribution perceived under the minimal length scale effect is derived via the generalized uncertainty principle. Here, the…

General Relativity and Quantum Cosmology · Physics 2023-12-08 Ali Övgün , Lemuel John F. Sese , Reggie C. Pantig