English
Related papers

Related papers: Generalized JMN Naked Singularity Models

200 papers

A distinguishable physical property between a naked singularity and a black-hole, formed during a gravitational collapse has important implications for both experimental and theoretical relativity. We examine the energy radiated during the…

General Relativity and Quantum Cosmology · Physics 2007-05-23 I. H. Dwivedi

In this paper, we derive the solutions of orbit equations for a class of naked singularity spacetimes, and compare these with timelike orbits, that is, particle trajectories in the Schwarzschild black hole spacetime. The Schwarzschild and…

General Relativity and Quantum Cosmology · Physics 2019-12-11 Parth Bambhaniya , Ashok B. Joshi , Dipanjan Dey , Pankaj S. Joshi

Classical general relativity predicts a singularity at the center of a black hole, where known laws of physics break down. This suggests the existence of deeper, yet unknown principles of Nature. Among various theoretical possibilities, one…

General Relativity and Quantum Cosmology · Physics 2025-04-22 Nihar Ranjan Ghosh , Malay K. Nandy

Recent observations of the Milky-way galactic center at various frequencies suggest a supermassive compact object. Generally, that supermassive compact object is assumed to be a `Black Hole', having more than four million solar masses. In…

General Relativity and Quantum Cosmology · Physics 2022-02-02 Saurabh , Parth Bambhaniya , Pankaj S. Joshi

In this paper we present a non-singular black hole model as a possible end-product of gravitational collapse. The depicted spacetime which is type [II,(II)], by Petrov classification, is an exact solution of the Einstein equations and…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Manasse R. Mbonye , Demosthenes Kazanas

This is the first of two papers where we study the asymptotics of the generalized Nariai solutions and its relation to the cosmic no-hair conjecture. According to the cosmic no-hair conjecture, generic expanding solutions of Einstein's…

General Relativity and Quantum Cosmology · Physics 2011-03-28 Florian Beyer

We study the optical appearance of a thin accretion disk around compact objects within the Einstein-Gauss-Bonnet gravity. Considering static spherically symmetric black holes and naked singularities we search for characteristic signatures…

General Relativity and Quantum Cosmology · Physics 2021-10-27 Galin Gyulchev , Petya Nedkova , Tsvetan Vetsov , Stoytcho Yazadjiev

We comment here on the results in Ref [4] that showed naked singularities in dynamical gravitational collapse of inhomogeneous dust to be stable but non-generic. The definition of genericity used there is reconsidered. We point out that…

General Relativity and Quantum Cosmology · Physics 2012-07-17 Ravindra V. Saraykar , Pankaj S. Joshi

We explore the possibilities of modeling a spherically symmetric static spacetime that can emerge as the end state of gravitational collapse, by considering it to be seeded by a composite fluid made of matter and a scalar field. In this…

General Relativity and Quantum Cosmology · Physics 2025-02-07 Debanjan Debnath , Dipanjan Dey , Kaushik Bhattacharya

We present a systematic method for constructing static, spherically symmetric regular spacetimes in general relativity satisfying the weak energy condition. Our approach relies on physically reasonable assumptions on the matter energy…

General Relativity and Quantum Cosmology · Physics 2026-05-12 Zi-Liang Wang , Emmanuele Battista

We consider the basic physical properties of matter forming a thin accretion disc in the static and spherically symmetric space-time metric of the vacuum $f(R)$ modified gravity models. The Lagrangian of the generalized gravity theory is…

General Relativity and Quantum Cosmology · Physics 2008-11-26 C. S. J. Pun , Z. Kovacs , T. Harko

We study the linear polarization from the accretion disk around weakly and strongly naked Janis-Newman-Winicour singularities. We consider an analytical toy model of thin magnetized fluid ring orbiting in the equatorial plane and emitting…

General Relativity and Quantum Cosmology · Physics 2023-03-28 Valentin Deliyski , Galin Gyulchev , Petya Nedkova , Stoytcho Yazadjiev

The process of the gravitational collapse might lead not only to a black hole but also to naked singularity formation. In this paper, we consider the generalized Vaidya spacetime with polytropic and generalized polytropic equations of…

General Relativity and Quantum Cosmology · Physics 2024-02-27 Vitalii Vertogradov

Motivated by the lack of rotating solutions sourced by matter in General Relativity as well as in modified gravity theories, we extend a recently discovered exact rotating solution of the minimal Einstein-scalar theory to its counterpart in…

General Relativity and Quantum Cosmology · Physics 2021-03-17 Wei-Hsiang Shao , Che-Yu Chen , Pisin Chen

We investigate all static spherically symmetric solutions in the context of general relativity surrounded by a minimally-coupled quintessence field, using dynamical system analysis. Applying the 1+1+2 formalism and introducing suitable…

General Relativity and Quantum Cosmology · Physics 2017-05-29 Miguel Cruz , Apratim Ganguly , Radouane Gannouji , Genly Leon , Emmanuel N. Saridakis

By imposing suitable junction conditions on a space-like hyper-surface, we obtain a two-parameter family of possible static configurations from gravitational collapse. These exemplify a new class of naked singularities. We show that these…

General Relativity and Quantum Cosmology · Physics 2020-02-11 Kaushik Bhattacharya , Dipanjan Dey , Arindam Mazumdar , Tapobrata Sarkar

We examine the role of the initial density and velocity distribution in the gravitational collapse of a spherical inhomogeneous dust cloud. Such a collapse is described by the Tolman-Bondi metric which has two free functions: the…

General Relativity and Quantum Cosmology · Physics 2009-10-22 T. P. Singh , P. S. Joshi

There are a number of publications on relativistic objects dealing either with black holes or naked singularities in the center. Here we show that there exist static spherically symmetric solutions of Einstein equations with a strongly…

General Relativity and Quantum Cosmology · Physics 2024-08-27 O. S. Stashko , V. I. Zhdanov

We develop here a new procedure within Einstein's theory of gravity to generate equilibrium configurations that result as the final state of gravitational collapse from regular initial conditions. As a simplification, we assume that the…

General Relativity and Quantum Cosmology · Physics 2015-05-28 Pankaj S. Joshi , Daniele Malafarina , Ramesh Narayan

Considering a strong field limit, we investigate the retrolensing phenomenon in the vicinity of a Janis-Newman-Winicour (JNW) naked singularity embedded in a scalar field. We assume that the light rays from a nearby source are reflected by…

General Relativity and Quantum Cosmology · Physics 2021-12-07 Gulmina Zaman Babar , Farruh Atamurotov , Abdullah Zaman Babar , Yen-Kheng Lim