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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

Physically relevant solutions in general relativity often contain spacetime singularities, which are typically interpreted as a sign of breakdown of the theory at high densities/curvatures. Hence, there has been a growing interest in…

General Relativity and Quantum Cosmology · Physics 2023-12-06 Swarnim Shashank

It is believed that in the near future, gravitational wave detections will become a promising tool not only to test gravity theories, but also to probe extremely curved spacetime regions in our universe, such as the surroundings of black…

General Relativity and Quantum Cosmology · Physics 2019-05-15 Che-Yu Chen , Pisin Chen

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

We attempt to study three significant tests of general relativity in higher dimensions both in commutative and non-commutative spaces. In the context of non-commutative geometry, we will consider a solution of the Einstein equation in…

General Relativity and Quantum Cosmology · Physics 2021-05-04 Davood Mahdavian Yekta , S. A. Alavi , Majid Karimabadi

A new spherically-symmetric solution for a gravitational field is found in the conformally-unimodular metric. It is shown, that the surface of the black hole horizon in the standard Schwarzschild metric can be squeezed to a point by…

General Relativity and Quantum Cosmology · Physics 2020-08-24 Sergey L. Cherkas , Vladimir L. Kalashnikov

The excitation of a black hole by infalling matter or radiation has been studied for a long time, mostly in linear perturbation theory. In this paper we study numerically the response of a Schwarzschild black hole to an incoming…

General Relativity and Quantum Cosmology · Physics 2021-09-22 Jörg Frauendiener , Chris Stevens

We study the geodesic motion of massless test particles in the background of a magnetic charged black hole spacetime in four dimensions in dilaton-Maxwell gravity. The behaviour of effective potential in view of the different values of…

General Relativity and Quantum Cosmology · Physics 2015-09-18 Ravi Shankar Kuniyal , Rashmi Uniyal , Hemwati Nandan , K. D. Purohit

X-ray reflection spectroscopy is a powerful tool for testing the Kerr hypothesis and probing the strong gravity regime around accreting black holes. Most tests of General Relativity (GR) assume that the spacetime around a black hole is…

General Relativity and Quantum Cosmology · Physics 2026-02-19 Leda Gao , Swarnim Shashank , Cosimo Bambi

In this work, we prove that the classical Schwarzschild-de Sitter spacetime is an exact solution of a class of weakly non-local, UV finite conformal quantum gravity theories, without the necessity of including a cosmological constant term…

General Relativity and Quantum Cosmology · Physics 2025-10-08 Diego A. Martínez-Valera

Maxwell's equations are invariant under both duality rotations and conformal transformations. Recently Bandos, Lechner, Sorokin, and Townsend have found a nonlinear generalisation of electrodynamics which possesses both of these symmetries.…

General Relativity and Quantum Cosmology · Physics 2020-12-14 Daniel Flores-Alfonso , Blanca Angélica González-Morales , Román Linares , Marco Maceda

We present a new constraint on the mass of the black hole in the active S0 galaxy NGC 5273. Due to the proximity of the galaxy at $16.6 \pm 2.1$ Mpc, we were able to resolve and extract the bulk motions of stars near the central black hole…

Astrophysics of Galaxies · Physics 2023-05-31 Katie A. Merrell , Eugene Vasiliev , Misty C. Bentz , Monica Valluri , Christopher A. Onken

Scalar-tensor theories of gravity generally violate the strong equivalence principle, namely compact objects have a suppressed coupling to the scalar force, causing them to fall slower. A black hole is the extreme example where such a…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-02 Jeremy Sakstein , Bhuvnesh Jain , Jeremy S. Heyl , Lam Hui

Finsler geometry is just riemannian geometry without the quadratic restriction[1]. In this paper, we study the motion of massive(non-zero rest mass) and massless particles for schwarzschild metric in finsler spacetime in the case of two…

General Relativity and Quantum Cosmology · Physics 2018-01-08 V. Sai sumith Reddy

We analyse the physics of nonlinear gravitational processes inside a spherical charged black hole perturbed by a self-gravitating massless scalar field. For this purpose we created an appropriate numerical code. Throughout the paper, in…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Jakob Hansen , Alexei Khokhlov , Igor Novikov

In the context of the recently proposed type-II minimally modified gravity theory, i.e. a metric theory of gravity with two local physical degrees of freedom that does not possess an Einstein frame, we study spherically symmetric vacuum…

General Relativity and Quantum Cosmology · Physics 2021-03-12 Antonio De Felice , Andreas Doll , François Larrouturou , Shinji Mukohyama

We combine notions of a maximal curvature scale in nature with that of a minimal curvature scale to construct a non-singular Schwarzschild-de Sitter black hole. We present an exact solution within the context of two-dimensional dilaton…

High Energy Physics - Theory · Physics 2018-11-13 Damien A. Easson

An exact time-dependent solution of a black hole is found in conformally invariant gravity on a warped Randall-Sundrum spacetime, by writing the metric $g_{\mu\nu}=\omega^{\frac{4}{n-2}}\tilde g_{\mu\nu}$. Here $\tilde g_{\mu\nu}$…

High Energy Physics - Theory · Physics 2021-07-19 Reinoud J. Slagter

We consider electromagnetic fields and charged particle dynamics around non-singular black holes in conformal gravity immersed in an external, asymptotically uniform magnetic field. First, we obtain analytic solutions of the electromagnetic…

General Relativity and Quantum Cosmology · Physics 2020-11-24 Bakhtiyor Narzilloev , Javlon Rayimbaev , Ahmadjon Abdujabbarov , Cosimo Bambi

In this work, we present the new technique for discussing the dynamical motion of neutral as well as charged particles in the absence/presence of magnetic field around the time conformal Schwarzschild black hole. Initially, we find the…

General Physics · Physics 2016-11-23 Abdul Jawad , Farhad Ali , M. Umair Shahzad , G. Abbas