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In light of the Event Horizon Telescope (EHT) images of the supermassive black holes $\textrm{Sgr A}^\star$ and $\textrm{M87}^\star$, we explore a potential supersymmetry suspicion within the observational data. Specifically, we investigate…

High Energy Physics - Theory · Physics 2024-09-05 L. Chakhchi , H. El Moumni , K. Masmar

In this paper, we investigate the optical properties of a charged black hole in Einstein-Maxwell-scalar (EMS) theory. We evaluate the shadow cast by the black hole and obtain analytical solutions for both the radius of the photon sphere and…

General Relativity and Quantum Cosmology · Physics 2024-07-29 Ahmad Al-Badawi , Mirzabek Alloqulov , Sanjar Shaymatov , Bobomurat Ahmedov

The images of supermassive black holes surrounded by optically-thin, radiatively-inefficient accretion flows, like those observed with the Event Horizon Telescope, are characterized by a bright ring of emission surrounding the black-hole…

High Energy Astrophysical Phenomena · Physics 2023-02-01 Ziri Younsi , Dimitrios Psaltis , Feryal Özel

We investigate the shadow cast by a regular black hole in scalar-tensor-vector mOdified gravity theory. This black hole differs from a Schwarzschild-Kerr black hole by the dimensionless parameter $\beta$. The size of the shadow depends on…

General Relativity and Quantum Cosmology · Physics 2024-09-09 Subhadip Sau , John W. Moffat

Higher dimensional theories admit astrophysical objects like supermassive black holes, which are rather different from standard ones, and their gravitational lensing features deviate from general relativity. It is well known that a black…

General Relativity and Quantum Cosmology · Physics 2018-05-31 Muhammed Amir , Balendra Pratap Singh , Sushant G. Ghosh

The spacetime singularities in classical general relativity predicted by the celebrated singularity theorems are formed at the end of gravitational collapse. Quantum gravity is the expected theory to resolve the singularity problem, but we…

General Relativity and Quantum Cosmology · Physics 2020-07-15 Sushant G. Ghosh , Muhammed Amir , Sunil D. Maharaj

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

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

Black holes in General Relativity are described by space-time metrics that are simpler in comparison to non-vacuum compact objects. However, given the universality of the gravitational pull, it is expected that dark matter accumulates…

General Relativity and Quantum Cosmology · Physics 2024-07-23 Caio F. B. Macedo , João Luís Rosa , Diego Rubiera-Garcia

Wormholes are hypothetical objects which can be black hole mimickers with strong gravitational fields. Recently, Wielgus et al. have constructed reflection-asymmetric thin-shell wormholes which are composed of the parts of a Schwarzschild…

General Relativity and Quantum Cosmology · Physics 2021-03-24 Naoki Tsukamoto

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

The Event Horizon Telescope, a global submillimeter wavelength very long baseline interferometry array, produced the first image of supermassive black hole M87* showing a ring of diameter $\theta_d= 42\pm 3\,\mu$as, inferred a black hole…

General Relativity and Quantum Cosmology · Physics 2020-06-18 Rahul Kumar , Amit Kumar , Sushant G. Ghosh

The Event Horizon Telescope collaboration has revealed the first direct image of a black hole, as per the shadow of a Kerr black hole of general relativity. However, other Kerr-like rotating black holes of modified gravity theories cannot…

General Relativity and Quantum Cosmology · Physics 2022-01-21 Misba Afrin , Sushant G. Ghosh

This study deals with the new class of embedded wormhole solutions in the background of general relativity. Two newly calculated wormhole solutions satisfy all the required properties. All the energy conditions are discussed through their…

General Relativity and Quantum Cosmology · Physics 2024-06-17 Niyaz Uddin Molla , Himanshu Chaudhary , Ujjal Debnath , G. Mustafa , S. K. Maurya

Following up on a recent analysis by Psaltis et al. [Phys. Rev. Lett. 125, 141104 (2020)], we show that the observed shadow size of M87$^*$ can be used to unambiguously and robustly constrain the black hole geometry in the vicinity of the…

General Relativity and Quantum Cosmology · Physics 2021-10-13 Sebastian H. Völkel , Enrico Barausse , Nicola Franchini , Avery E. Broderick

Black holes with dyonic charges in Einstein-Maxwell-dilaton-axion supergravity theory are revisited in the context of black hole shadows. We consider static as well as rotating (namely the dyonic Kerr-Sen) black holes. The matter…

General Relativity and Quantum Cosmology · Physics 2023-08-08 Soumya Jana , Sayan Kar

We have studied photon motion around axially symmetric rotating Kerr black hole in the presence of plasma with radial power-law density. It is shown that in the presence of plasma the observed shape and size of shadow changes depending on…

General Relativity and Quantum Cosmology · Physics 2015-10-21 Farruh Atamurotov , Bobomurat Ahmedov , Ahmadjon Abdujabbarov

We explore the shadow of certain class of rotating traversable wormholes within classical general relativity. The images depend on the angular momentum of the wormhole, and the inclination angle of the observer. We compare the results with…

General Relativity and Quantum Cosmology · Physics 2015-06-16 Petya G. Nedkova , Vassil Tinchev , Stoytcho S. Yazadjiev

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

The spacetime satisfying the flat curve condition for galaxies is shown to be the zero mass limit of the dilaton blackhole with an exponential potential. We derive the geodesic equations and by studying rotational curves and light…

General Relativity and Quantum Cosmology · Physics 2019-03-06 Yen-Kheng Lim