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Related papers: Shadows around the q-metric

200 papers

We present, in an explicit form, the metric for all spherically symmetric Schwarzschild-Bach black holes in Einstein-Weyl theory. In addition to the black hole mass, this complete family of spacetimes involves a parameter that encodes the…

General Relativity and Quantum Cosmology · Physics 2024-03-19 Jiri Podolsky , Robert Svarc , Vojtech Pravda , Alena Pravdova

This paper investigates photon motion in black hole of Einstein-Maxwell-dilaton theory, exploring black hole shadows and observational characteristics under various accretion models. We first give the relation of the event horizon, photon…

General Relativity and Quantum Cosmology · Physics 2025-12-16 Junlin Qin , Hong-Er Gong , Yusen Wang , Zhan-Feng Mai , Bofeng Wu , Sen Guo , Enwei Liang

We give a full metric describing the gravitational field of a static and axisymmetric thin disk without radial pressure encircling a Schwarzschild black hole. The disk density profiles are astrophysically realistic, stretching from the…

General Relativity and Quantum Cosmology · Physics 2022-12-13 Petr Kotlařík , David Kofroň

It is well known that a hypothetical compact object that looks like an Einsteinian (Schwarzschild or Kerr) black hole everywhere except a small region near its surface should have the ringdown profile predicted by the Einstein theory at…

General Relativity and Quantum Cosmology · Physics 2019-01-23 R. A. Konoplya , Z. Stuchlík , A. Zhidenko

We continue the study of the non-metric theory of gravity introduced in hep-th/0611182 and gr-qc/0703002 and obtain its general spherically symmetric vacuum solution. It respects the analog of the Birkhoff theorem, i.e., the vacuum…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Kirill Krasnov , Yuri Shtanov

We investigate a generalized Chaplygin-like gas with an anisotropic equation of state, characterizing a dark fluid within which a static spherically symmetric black hole is assumed. By solving the Einstein equations for this black hole…

General Relativity and Quantum Cosmology · Physics 2024-08-05 Mohsen Fathi , J. R. Villanueva , Gilberto Aguilar-Pérez , Miguel Cruz

We investigate the physical properties of equilibrium sequences of non-self-gravitating surfaces that characterize thick disks around a rotating deformed compact object described by a stationary generalization of the static q-metric. The…

General Relativity and Quantum Cosmology · Physics 2025-02-14 Shokoufe Faraji , Audrey Trova , Hernando Quevedo

Metric of axially symmetric asymptotically flat black holes in an arbitrary metric theory of gravity can be represented in the general form which depends on infinite number of parameters. We constrain this general class of metrics by…

General Relativity and Quantum Cosmology · Physics 2021-05-20 R. A. Konoplya , A. Zhidenko

Among the three known types of static solutions proposed within the Hamiltonian constraint approach to effective quantum gravity (EQG), the first two have been extensively investigated, whereas the third type-which preserves general…

General Relativity and Quantum Cosmology · Physics 2025-11-18 Wentao Liu , Di Wu , Jieci Wang

We consider null and time-like geodesics around a spherically symmetric, non-rotating Coherent Quantum Black Hole (CQBH). The classical limit of the geometry of CQBH departs from that of the Schwarzschild spacetime at short scales and…

General Relativity and Quantum Cosmology · Physics 2024-06-10 Abdybek Urmanov , Hrishikesh Chakrabarty , Daniele Malafarina

We present a new solution in Einstein's General Relativity representing a Schwarzschild black hole immersed in a rotating universe. Such a solution is constructed analytically by means of the last unexplored Lie point symmetry of the Ernst…

General Relativity and Quantum Cosmology · Physics 2024-02-08 Marco Astorino , Riccardo Martelli , Adriano Viganò

The search for solutions of Einstein's equations representing relativistic cosmological models with a discrete matter content has been remarkably fruitful in the last decade. In this review we discuss the progress made in the study of a…

General Relativity and Quantum Cosmology · Physics 2018-08-08 Eloisa Bentivegna , Timothy Clifton , Jessie Durk , Mikołaj Korzyński , Kjell Rosquist

We calculate the photon sphere $r_{ph}$ and critical curve $b_c$ for the quantum corrected Schwarzschild black hole, finding that they violate an universal inequalities proved for asymptotically flat black holes which satisfy null energy…

General Relativity and Quantum Cosmology · Physics 2021-09-01 Jun Peng , Minyong Guo , Xing-Hui Feng

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

Contents: 1) Introduction and a few excursions [A word on the role of explicit solutions in other parts of physics and astrophysics. Einstein's field equations. "Just so" notes on the simplest solutions: The Minkowski, de Sitter and anti-de…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Jiri Bicak

Using a continued fraction ansatz we obtain an analytic approximation for a spherically symmetric black hole solution to Einsteinian Quartic Gravity (EQG), the next simplest Generalized Quasi-Topological Gravity (GQTG) after Einsteinian…

General Relativity and Quantum Cosmology · Physics 2020-09-02 H. Khodabakhshi , A. Giaimo , Robert B. Mann

We study gravitational lensing by a recently proposed black hole solution in Loop Quantum Gravity. We highlight the fact that the quantum gravity corrections to the Schwarzschild metric in this model evade the `mass suppression' effects…

General Relativity and Quantum Cosmology · Physics 2015-03-16 Satyabrata Sahu , Kinjalk Lochan , D. Narasimha

We obtained new hairy black hole solutions in Einstein-scalar theory, including asymptotic flat, de Sitter and anti-de Sitter black holes. The theory is inspired by Ref. [1], where traversable wormhole solutions from an Einstein-phantom…

General Relativity and Quantum Cosmology · Physics 2024-03-19 Xiao-Ping Rao , Hyat Huang , Jinbo Yang

The Event Horizon Telescope (EHT) has recently observed the image and shadow of the supermassive compact object Sagittarius A$^*$ (Sgr A$^*$). According to the EHT collaboration, the observed image is consistent with the expected appearance…

General Relativity and Quantum Cosmology · Physics 2023-05-29 Rajibul Shaikh

We analyze gravitational lensing, in particular the shadow and photon rings, in the Ernst spacetime, also known as the Schwarzschild-Melvin spacetime, which describes a Schwarzschild black hole immersed in a homogenous magnetic field.…

General Relativity and Quantum Cosmology · Physics 2025-12-30 Muhammad Haider Khan , Volker Perlick