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Related papers: Shadow Geometry of Kerr Naked Singularities

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Naked singularities are hypothetical astrophysical entities featuring gravitational singularities without event horizons. In this study, we analyze the shadow properties of Kerr Modified Gravity (Kerr MOG) naked singularities (KMNSs). We…

General Relativity and Quantum Cosmology · Physics 2025-12-25 Saira Yasmin , Mubasher Jamil

We present a detailed study of higher-order photon rings of an accreting Kerr naked singularity (KNS) with dimensionless spin parameter $a=1.01$; i.e., a horizonless, overly spinning compact object. Motivated by horizon-scale…

High Energy Astrophysical Phenomena · Physics 2025-11-27 Hina Suzuki , Yosuke Mizuno , Akhil Uniyal , Indu Kalpa Dihingia , Tintin Nguyen , Chi-kwan Chan

We study null and timelike constant radii geodesics in the environment of an over-spinning putative Kerr-type naked singularity. We are particularly interested in two topics: first, the differences of the shadows of the naked rotating…

General Relativity and Quantum Cosmology · Physics 2024-02-20 Aydin Tavlayan , Bayram Tekin

In this paper, we investigate the light trajectories and shadow properties in the rotating version of null naked singularity (NNS) spacetime which is derived using the Newman- Janis algorithm without complexification method. We discuss some…

General Relativity and Quantum Cosmology · Physics 2022-09-21 Vishva Patel , Divya Tahelyani , Ashok B. Joshi , Dipanjan Dey , Pankaj S. Joshi

The Event Horizon Telescope (EHT) collaboration unveiled event-horizon-scale images of the supermassive black holes (SMBHs) M87* and Sgr A*, revealing a dark brightness depression, namely the black hole shadow, whose shape and size may…

General Relativity and Quantum Cosmology · Physics 2023-07-27 Misba Afrin , Sushant G. Ghosh

We study bound orbits near the centres of static, spherically symmetric, asymptotically flat configurations of a self-gravitating scalar field minimally coupled to gravity. In our approach, a nonlinear scalar field is considered as an…

General Relativity and Quantum Cosmology · Physics 2019-08-29 I. M. Potashov , Ju. V. Tchemarina , A. N. Tsirulev

Recently, new exploratory channels have opened up for the physics of highly compact objects, such as gravitational waves and black hole shadows. Moreover, more precise analysis and observations are now possible in the physics of accretion…

General Relativity and Quantum Cosmology · Physics 2024-10-01 D. Pugliese , H. Quevedo

In a recent work on rotating black hole shadows [Phys. Rev. D{\bf 101}, 084029 (2020)], we proposed a new approach for calculating size and shape of the shadows in terms of astrometrical observables with respect to finite-distance…

General Relativity and Quantum Cosmology · Physics 2020-08-11 Zhe Chang , Qing-Hua Zhu

We construct asymptotically flat, spinning, regular on and outside an event horizon, scalarised black holes (SBHs) in extended scalar-tensor-Gauss-Bonnet models. They reduce to Kerr BHs when the scalar field vanishes. For an illustrative…

General Relativity and Quantum Cosmology · Physics 2019-07-10 Pedro V. P. Cunha , Carlos A. R. Herdeiro , Eugen Radu

Thanks to the release of the extraordinary EHT image of shadow attributed to the M87* supermassive black hole (SMBH), we have a novel window to assess the validity of fundamental physics in the strong-field regime. Motivated by this, we…

General Relativity and Quantum Cosmology · Physics 2021-09-22 Mohsen Khodadi , Gaetano Lambiase , David F. Mota

Using backwards ray tracing, we study the shadows of Kerr black holes with scalar hair (KBHsSH). KBHsSH interpolate continuously between Kerr BHs and boson stars (BSs), so we start by investigating the lensing of light due to BSs. Moving…

General Relativity and Quantum Cosmology · Physics 2015-11-25 Pedro V. P. Cunha , Carlos A. R. Herdeiro , Eugen Radu , Helgi F. Runarsson

We construct shadows of superspinars described by the revisited Kerr-de Sitter (rKdS) naked singularity (NS) spacetimes and compare them with those of the standard KdSNS spacetimes. For all the classes of the rKdSNS spacetimes we determine…

General Relativity and Quantum Cosmology · Physics 2026-05-29 Daniel Charbulák , Zdeněk Stuchlík

In this work, we investigate the shadow properties of the Kerr-Newman-Anti-de Sitter black hole coupled to a nonlinear electrodynamics. We construct the shadow by employing the celestial coordinate approach for observers located at finite…

General Relativity and Quantum Cosmology · Physics 2025-08-20 Mohsen Fathi

For the Kerr naked singularity (KNS) spacetimes, we study properties of spherical photon orbits (SPOs) confined to constant Boyer-Lindquist radius r. Some new features of the SPOs are found, having no counterparts in the Kerr black hole…

General Relativity and Quantum Cosmology · Physics 2018-11-08 Daniel Charbulák , Zdeněk Stuchlík

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

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

This work is geared towards analysis of shadows cast by Kerr-de Sitter (KdS) and Kerr-de Sitter Revisited (RKdS) black holes. Considering observers in the vicinity of the static radius, we derive the impact parameters defining the apparent…

General Relativity and Quantum Cosmology · Physics 2022-05-17 Eunice Omwoyo , Humberto Belich , Júlio C. Fabris , Hermano Velten

The recent detection of gravitational waves from black hole coalescences and the first image of the black hole shadow enhance the possibilities of testing gravitational theories in the strong-field regime. In this paper, we study the…

General Relativity and Quantum Cosmology · Physics 2020-05-27 Che-Yu Chen

We consider the possibility that astrophysical Black Holes (BHs) can violate the Kerr bound; i.e., they can have angular momentum greater than BH mass, $J > M$. We discuss implications on the BH apparent shape. Even if the bound is violated…

Astrophysics · Physics 2009-02-06 Cosimo Bambi , Katherine Freese

We study here the precession of the spin of a test gyroscope attached to a stationary observer in the Kerr spacetime, specifically, to distinguish naked singularity (NS) from black hole (BH). It was shown recently that for gyros attached to…

General Relativity and Quantum Cosmology · Physics 2017-04-14 Chandrachur Chakraborty , Prashant Kocherlakota , Mandar Patil , Sudip Bhattacharyya , Pankaj S. Joshi , Andrzej Królak
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