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We present a solution for rotating black holes in massive gravity. We first give a solution of massive gravity with one dynamical metric. Both metrics of this solution are expressed in the advanced Eddington-Finkelstein-like coordinates:…

General Relativity and Quantum Cosmology · Physics 2014-11-07 Eugeny Babichev , Alessandro Fabbri

Weyl conformal gravity was originally proposed in the early twentieth century as an attempt to unify gravitation and electromagnetism. Since 1989, renewed interest in this fourth-order theory of gravity has emerged following the discovery…

General Relativity and Quantum Cosmology · Physics 2026-04-17 Cristina Blaga , Paul A. Blaga

We study the formation and the evaporation of a spherically symmetric black hole in conformal gravity. From the collapse of a spherically symmetric thin shell of radiation, we find a singularity-free non-rotating black hole. This black hole…

General Relativity and Quantum Cosmology · Physics 2018-09-03 Cosimo Bambi , Leonardo Modesto , Shiladitya Porey , Leslaw Rachwal

We present the first exact and analytical solution in General Relativity describing an equilibrium configuration for two stationary black holes. The metric models two collinear extremal Kerr black holes immersed in an external and…

General Relativity and Quantum Cosmology · Physics 2025-09-23 Marco Astorino , Matilde Torresan

In this work we find analytical solutions to the null geodesics in the hyperbolic topological black hole spacetime of conformal Weyl gravity in an invariant $2$-plane given by the orbits of an azimuthal Killing vector. Exact expressions for…

General Relativity and Quantum Cosmology · Physics 2018-08-24 Graeme Candlish , Marco Olivares , Constanza Osses , J. R. Villanueva

We present, in closed analytic form, a general stationary, slowly rotating black hole, which is solution to a large class of alternative theories of gravity in four dimensions. In these theories, the Einstein-Hilbert action is supplemented…

General Relativity and Quantum Cosmology · Physics 2011-10-27 Paolo Pani , Caio F. B. Macedo , Luis C. B. Crispino , Vitor Cardoso

The static vacuum spherically symmetric solutions in massive gravity are obtained both analytically and numerically. The solutions depend on two parameters (integration constants): the mass M (or, equivalently, the Schwarzschild radius),…

General Relativity and Quantum Cosmology · Physics 2011-06-10 Michael V. Bebronne , Peter G. Tinyakov

In the context of f(R) theories of gravity, we address the problem of finding a rotating charged black hole solution in the case of constant curvature. The new metric is obtained by solving the field equations and we show that the behavior…

General Relativity and Quantum Cosmology · Physics 2015-05-30 Alexis Larranaga

The formation of spacetime singularities is a quite common phenomenon in General Relativity and it is regulated by specific theorems. It is widely believed that spacetime singularities do not exist in Nature, but that they represent a…

General Relativity and Quantum Cosmology · Physics 2013-04-08 Cosimo Bambi , Leonardo Modesto

We propose a new parametric framework to describe in generic metric theories of gravity the spacetime of spherically symmetric and slowly rotating black holes. In contrast to similar approaches proposed so far, we do not use a Taylor…

General Relativity and Quantum Cosmology · Physics 2014-10-09 Luciano Rezzolla , Alexander Zhidenko

The analysis of the properties of the X-ray radiation emitted from geometrically thin accretion disks around black holes can be a powerful tool to test General Relativity in the strong field regime. This chapter reviews the state-of-the-art…

General Relativity and Quantum Cosmology · Physics 2024-07-12 Cosimo Bambi

No Kerr-like exact solution has yet been found in Chern-Simons modified gravity. Intrigued by this absence, we study stationary and axisymmetric metrics that could represent the exterior field of spinning black holes. For the standard…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Daniel Grumiller , Nicolas Yunes

The prediction of spacetime singularities, regions of infinite curvature where classical physics breaks down, is one of the most profound challenges in General Relativity (GR). In particular, black hole solutions such as the Schwarzschild…

General Relativity and Quantum Cosmology · Physics 2025-11-18 Jose Pinedo Soto

Rapidly rotating black hole solutions in theories beyond general relativity play a key role in experimental gravity, as they allow us to compute observables in extreme spacetimes that deviate from the predictions of general relativity. Such…

General Relativity and Quantum Cosmology · Physics 2016-11-29 Robert McNees , Leo C. Stein , Nicolás Yunes

In this work, we obtain the analytically approximation of static, spherically symmetric black hole solutions to Einstein$-$Weyl squared gravity by using the continued fraction expansion method. The black hole solutions are found for various…

General Relativity and Quantum Cosmology · Physics 2025-01-06 Seyed Naseh Sajadi , Supakchai Ponglertsakul

In this paper, we study the physical properties of black holes in the framework of the recently proposed Einstien-Bel-Robinson gravity. We show that interestingly the theory propagates a transverse and massive graviton on a maximally…

General Relativity and Quantum Cosmology · Physics 2024-11-12 S. N. Sajadi , Robert B. Mann , H. Sheikhahmadi , M. Khademi

We present a parametric study of the spacetime structures obtainable in Weyl conformal gravity's dyonic Reissner-Nordstr\"{o}m solution. We derive expressions for photon sphere radii and horizons for this metric in terms of the conformal…

General Relativity and Quantum Cosmology · Physics 2026-02-05 Reinosuke Kusano , Miguel Yulo Asuncion , Keith Horne

We obtain exact black hole solutions for static and spherically symmetric sources in a Weyl conformal gauge theory of gravity. We consider a quadratic gravitational action built from the Weyl tensor within a dilation geometry. In a…

General Relativity and Quantum Cosmology · Physics 2025-09-29 Leandro A. Lessa , Caio F. B. Macedo , Manoel M. Ferreira

A simple modification to Einstein's theory of gravity in terms of a non-Riemannian connection is examined. A new tensor-variational approach yields field equations that possess a covariance similar to the gauge covariance of…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Robin W Tucker , Charles Wang

Inspired by the observations of supermassive black hole M87* in \emph{Event Horizon Telescope }(EHT) experiment, a remarkable surge in black hole physics is to use the black hole shadow's observables to distinguish general relativity (GR)…

General Relativity and Quantum Cosmology · Physics 2022-09-20 Yuan Meng , Xiao-Mei Kuang , Zi-Yu Tang