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Related papers: Shadow of a naked singularity

200 papers

In this work, we study the optical properties of a class of magnetically charged rotating black hole spacetimes. The black holes in question are assumed to be immersed in the quintessence field, and subsequently, the resulting black hole…

General Relativity and Quantum Cosmology · Physics 2022-06-15 Chengxiang Sun , Yunqi Liu , Wei-Liang Qian , Ruihong Yue

This paper investigates the shadow of a charged rotating non-commutative black hole. For this purpose, we first formulate the null geodesics and study the effects of non-commutative charge on the photon orbit. We then explore the effect of…

General Relativity and Quantum Cosmology · Physics 2016-12-21 M. Sharif , Sehrish Iftikhar

Recent observations by the Event Horizon Telescope (EHT) indicate that the shadow of the compact object at our Galaxy's center (Sgr A*) closely resembles that of a Schwarzschild black hole. However, identifying the presence and exact…

General Relativity and Quantum Cosmology · Physics 2025-12-24 Ashok B. Joshi , Vishva Patel , Parth C. Varasani

We explore a novel scenario in which a quantum-induced ghost instability drives the natural evolution of an evaporating Schwarzschild black hole toward a stable naked singularity. This process, arising from quadratic curvature corrections…

General Relativity and Quantum Cosmology · Physics 2025-05-09 Alfio Bonanno , Samuele Silveravalle

The gravitational collapse of a pressureless fluid in general relativity (Oppenheimer-Snyder collapse) results in a black hole. The study of the same phenomenon in the brane-world scenario has shown that the exterior of the collapsing dust…

High Energy Physics - Theory · Physics 2010-10-27 László Á. Gergely

Direct imaging of supermassive black holes (SMBHs) at event horizon scale resolutions, as recently done by the Event Horizon Telescope, allows for testing alternative models to SMBHs such as Kerr naked singularities (KNSs). We demonstrate…

High Energy Astrophysical Phenomena · Physics 2023-08-28 Bao Nguyen , Pierre Christian , Chi-kwan Chan

Causal concept for the general black hole shadow is investigated, instead of the photon sphere. We define several `wandering null geodesics' as complete null geodesics accompanied by repetitive conjugate points, which would correspond to…

General Relativity and Quantum Cosmology · Physics 2020-10-15 Masaru Siino

Motivated by the recent argument that in the TeV-scale gravity trans-Planckian domains of spacetime as effective naked singularities would be generated by high-energy particle (and black-hole) collisions, we investigate the quantum particle…

General Relativity and Quantum Cosmology · Physics 2012-03-06 Umpei Miyamoto , Hiroya Nemoto , Masahiro Shimano

We study strong gravitational lensing in a static, spherically symmetric, naked singularity spacetime, without a photon sphere. The nature of the singularity is found to be lightlike. We discuss the characteristic lensing features of this…

General Relativity and Quantum Cosmology · Physics 2020-09-25 Suvankar Paul

Repulsive gravity is a well known characteristic of naked singularities. In this work, we explore light surfaces and find new effects of repulsive gravity. We compare Kerr naked singularities with the corresponding black hole counterparts…

General Relativity and Quantum Cosmology · Physics 2022-03-23 Daniela Pugliese , Hernando Quevedo

Mimetic gravity has gained significant appeal in cosmological contexts, but static spherically symmetric space-times within the baseline theory are highly non-trivial: the two natural solutions are a naked singularity and a black hole…

General Relativity and Quantum Cosmology · Physics 2024-11-07 Mohsen Khodadi , Sunny Vagnozzi , Javad T. Firouzjaee

In this work, we have investigated the outcome of gravitational collapse in Husain space-time in the presence of electro-magnetic and a scalar field with potential. In order to study the nature of the singularity, global behavior of radial…

General Relativity and Quantum Cosmology · Physics 2012-03-12 Ujjal Debnath , Prabir Rudra , Ritabrata Biswas

In this paper, by exploring the photon motion in the region near the Bardeen black hole, the shadow and observation properties of the black hole surrounded by various accretion models are studied. We analyzed the changes in shadow imaging…

High Energy Physics - Theory · Physics 2022-08-17 Ke-Jian He , Sen Guo , Shuang-Cheng Tan , Guo-Ping Li

Global visibility of naked singularities is analyzed here for a class of spherically symmetric spacetimes, extending previous studies - limited to inhomogeneous dust cloud collapse - to more physical valid situations in which pressures are…

General Relativity and Quantum Cosmology · Physics 2009-11-11 R. Giambo'

We construct an approximate solution which describes the gravitational emission from a naked singularity formed by the gravitational collapse of a cylindrical thick shell composed of dust. The assumed situation is that the collapsing speed…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Ken-ichi Nakao , Yoshiyuki Morisawa

We study the shadow cast by the H$D$ Schwarzschild-Tangherlini black hole, and analytically calculate the influence of extra dimensions on the shadow of a black hole. A black hole casts a shadow as an optical appearance because of its…

General Relativity and Quantum Cosmology · Physics 2017-07-25 Balendra Pratap Singh , Sushant G. Ghosh

Using the general formalism for spherical gravitational collapse developed in [1], we investigate here the final fate of a spherical distribution of a matter cloud, where radial pressures vanish but tangential pressures are non-zero. Within…

General Relativity and Quantum Cosmology · Physics 2011-05-09 Daniele Malafarina , Pankaj S. Joshi

There are known models of spherical gravitational collapse in which the collapse ends in a naked shell-focusing singularity for some initial data. If a massless scalar field is quantized on the classical background provided by such a star,…

General Relativity and Quantum Cosmology · Physics 2009-12-31 Tomohiro Harada , Hideo Iguchi , Ken-ichi Nakao , T. P. Singh , Takahiro Tanaka , Cenalo Vaz

A major issue in general relativity and blackhole physics today is to determine the conditions when the spacetime singularities forming as end-states of gravitational collapse are visible to external observers, and when these are hidden…

General Relativity and Quantum Cosmology · Physics 2025-08-21 Koushiki , Pankaj S. Joshi

We investigate the shadow cast by a rotating braneworld black hole, in the Randall-Sundrum scenario. In addition to the angular momentum, the tidal charge term deforms the shape of the shadow. For a given value of the rotation parameter,…

General Relativity and Quantum Cosmology · Physics 2012-03-19 Leonardo Amarilla , Ernesto F. Eiroa