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Related papers: Black hole shadow to probe modified gravity

200 papers

In this paper, we explore the Kerr-Sen-Taub-NUT spacetime with the inclusion of the Manko-Ruiz parameter. We demonstrate the separability of the Hamilton-Jacobi equation for a classical test particle in this spacetime and, using the null…

General Relativity and Quantum Cosmology · Physics 2025-04-15 Haryanto M. Siahaan

This work investigates the optical properties of a static, spherically symmetric, electrically charged black hole in f(R) gravity coupled to Euler-Heisenberg(EH) nonlinear electrodynamics(NLED). By analyzing photon trajectories in this…

General Relativity and Quantum Cosmology · Physics 2026-01-16 Khadije Jafarzade , Saira Yasmin , Mubasher Jamil

We study the shadow of rotating charge black holes in the presence of quintessence. The shadow of a rotating black hole is a distorted circle and in our study, we find that the shape and size of the black hole shadow depend upon four…

General Relativity and Quantum Cosmology · Physics 2022-05-05 Balendra Pratap Singh

A black hole casts a shadow as an optical appearance because of its strong gravitational field. We study the shadow cast by the five-dimensional Myers-Perry black hole with equal rotation parameters. We demonstrate that the null geodesic…

General Relativity and Quantum Cosmology · Physics 2015-06-22 Uma Papnoi , Farruh Atamurotov , Sushant G. Ghosh , Bobomurat Ahmedov

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

Using an improved version of the Newman-Janis algorithm, we obtain metrics of rotating black holes for a set of extended gravity theories that extend general relativity in different ways: the Horndeski model, the bumblebee model, the…

General Relativity and Quantum Cosmology · Physics 2025-03-24 Stanislav Alexeyev , Oleg Zenin , Artem Baiderin

We study shadow aspects of superentropic black holes in four dimensions. Using Hamilton-Jacobi formalism, we first get the null geodesic equations. In the celestial coordinate framework relying on fixed positions of observers, we…

High Energy Physics - Theory · Physics 2022-07-27 A. Belhaj , H. Belmahi , M. Benali

Recently, a covariant spherically symmetric model of a black hole within the framework of loop quantum gravity (LQG), characterized by a quantum parameter $r_0$ or $\lambda$, has been proposed. To derive constraints on the LQG-corrected…

General Relativity and Quantum Cosmology · Physics 2024-01-10 Ruo-Ting Chen , Shulan Li , Li-Gang Zhu , Jian-Pin Wu

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

We use data from M87* central black hole shadow, as well as from the S2 star observations, in order to extract constraints on Barrow entropy. The latter is a modified entropy arising from quantum-gravitational effects on the black hole…

General Relativity and Quantum Cosmology · Physics 2022-02-08 Kimet Jusufi , Mustapha Azreg-Aïnou , Mubasher Jamil , Emmanuel N. Saridakis

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

Vagnozzi et al. constrained the additional parameter of spacetimes with a photon sphere from the observation of the shadow of Sagittarius A* under the assumption that a distance to the Sagittarius A* and its mass parameter was estimated…

General Relativity and Quantum Cosmology · Physics 2023-10-19 Naoki Tsukamoto

Shadows of black holes surrounded by an optically thin emitting medium have been extensively discussed in the literature. The Hioki-Maeda algorithm is a simple recipe to characterize the shape of these shadows and determine the parameters…

High Energy Astrophysical Phenomena · Physics 2015-12-04 Lingyun Yang , Zilong Li

In previous work we have developed a model-independent, effective description of quantum deformed, spherically symmetric and static black holes in four dimensions. The deformations of the metric are captured by two functions of the physical…

General Relativity and Quantum Cosmology · Physics 2024-12-19 Manuel Del Piano , Stefan Hohenegger , Francesco Sannino

In this article, we investigate the impact of cosmological parameters on black holes using an exact solution to Einstein's equations that satisfies the Whittaker equation of state. We examine a spherically symmetric black hole in the…

General Relativity and Quantum Cosmology · Physics 2024-04-26 Santanu Tripathy , K Rajesh Nayak

A large international effort is under way to assess the presence of a shadow in the radio emission from the compact source at the centre of our Galaxy, Sagittarius A$^*$ (Sgr A$^*$). If detected, this shadow would provide the first direct…

General Relativity and Quantum Cosmology · Physics 2016-06-03 A. A. Abdujabbarov , L. Rezzolla , B. J. Ahmedov

We analytically investigate the shadows cast by rotating black holes in the asymptotically safe gravity (ASG) by deriving complete null geodesics and observables using the Hamilton-Jacobi equation and Carter separable method. It turns out…

General Relativity and Quantum Cosmology · Physics 2020-07-13 Rahul Kumar , Balendra Pratap Singh , Sushant G. Ghosh

The Chern-Simons modification to general relativity in four dimensions consists of adding to the Einstein-Hilbert term a scalar field that couples to the first class Pontryagin density. In this theory, which has attracted considerable…

General Relativity and Quantum Cosmology · Physics 2010-06-29 Leonardo Amarilla , Ernesto F. Eiroa , Gaston Giribet

The presence of a quintessence-like field can influence the black hole shadow through three primary mechanisms: the dynamics of accretion flows, the trajectories of photons, and the motion of observers. Unlike standard shadow analyses that…

General Relativity and Quantum Cosmology · Physics 2026-04-13 Ji-Wen Li , Zi-Liang Wang , Tao-Tao Sui

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