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Related papers: On the Null Trajectories in Conformal Weyl Gravity

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The null geodesic equations that describe motion of photons in Kerr spacetime are solved exactly in the presence of the cosmological constant $\Lambda$. The exact solution for the deflection angle for generic light orbits (i.e. non-polar,…

General Relativity and Quantum Cosmology · Physics 2011-04-08 G. V. Kraniotis

Weyl's conformal theory of gravity is an extension of Einstein's theory of general relativity which associates metrics with 1-forms . In the case of locally integrable (closed non-exact) 1-forms the spacetime manifolds are no more simply…

General Relativity and Quantum Cosmology · Physics 2022-06-09 Michel Duneau

One of the best ways to understand the gravitation of a massive object is by studying the photon's motion around it. We study the null geodesic of a regular black hole in anti-de Sitter spacetime, including a Gaussian matter distribution.…

General Relativity and Quantum Cosmology · Physics 2021-09-21 Abolhassan Mohammadi , N. Doustimotlagh , Tayeb Golanbari , Behrooz Malakolkalami , Shahram Jalalzadeh

We have studied null geodesics of the charged black hole surrounded by quintessence. Quintessence is a candidate for dark energy and is represented by a scalar field. Here, we have done a detailed study of the photon trajectories. The exact…

General Relativity and Quantum Cosmology · Physics 2015-09-17 Sharmanthie Fernando , Scott Meadows , Kevon Reis

The advanced state of cosmological observations constantly tests the alternative theories of gravity that originate from Einstein's theory. However, this is not restricted to modifications to general relativity. In this sense, we work in…

General Relativity and Quantum Cosmology · Physics 2020-11-10 Mohsen Fathi , Mona Kariminezhad , Marco Olivares , J. R. Villanueva

We study black hole shadows in nonminimally coupled Weyl connection gravity, a metric-affine extension of general relativity in which spacetime is described by a metric and a Weyl vector field encoding non-metricity. Despite going beyond…

General Relativity and Quantum Cosmology · Physics 2026-03-10 Cláudio Gomes , Margarida Lima , Francisco S. N. Lobo , Luís F. D. da Silva

We investigate the cosmological evolution for the physical parameters in Weyl integrable gravity in a Friedmann--Lema\^{\i}tre--Robertson--Walker universe with zero spatially curvature. For the matter component, we assume that it is an…

General Relativity and Quantum Cosmology · Physics 2021-12-02 Andronikos Paliathanasis

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

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

We show that Einstein's conformal gravity is able to explain simply on the geometric ground the galactic rotation curves without need to introduce any modification in both the gravitational as well as in the matter sector of the theory. The…

General Relativity and Quantum Cosmology · Physics 2021-12-09 Leonardo Modesto , Tian Zhou , Qiang Li

In any conformally invariant gravitational theory, the space of exact solutions is greatly enlarged. Therefore, we cannot exclude the Weyl's conformal invariance to be spontaneously broken to spherically symmetric vacuum solutions that…

General Relativity and Quantum Cosmology · Physics 2025-06-03 Leonardo Modesto , Ali Akil , Cosimo Bambi

We propose a novel test of gravity that combines galaxy clustering with gravitational lensing. In general relativity, the evolution of matter density fluctuations and of the Weyl potential -- the sum of spatial and temporal distortions of…

Cosmology and Nongalactic Astrophysics · Physics 2025-06-06 Camille Bonvin , Nastassia Grimm , Isaac Tutusaus

We consider the motion of test particles in the spacetime of a black hole in f(R) gravity. The complete set of analytic solutions of the geodesic equation in the spacetime of this black hole are presented. The geodesic equations are solved…

General Relativity and Quantum Cosmology · Physics 2015-08-19 Saheb Soroushfar , Reza Saffari , Jutta Kunz , Claus Lämmerzahl

In this paper, we investigate the geodesic motion of massive and massless test particles in the vicinity of a black hole space-time surrounded by perfect fluid (quintessence, dust, radiation, cosmological constant and phantom) in Rastall…

General Relativity and Quantum Cosmology · Physics 2021-02-15 Saheb Soroushfar , Maryam Afrooz

We examine the viability of Weyl conformal gravity as an alternative to the general theory of relativity. By using the extended rotation curve of the Milky Way and velocity dispersions of four globular clusters, we show that Weyl gravity…

General Relativity and Quantum Cosmology · Physics 2018-12-19 Koushik Dutta , Tousif Islam

It has recently been pointed out that one can construct invertible conformal transformations with a parity-violating conformal factor, which can be employed to generate a novel class of parity-violating ghost-free metric theories from…

General Relativity and Quantum Cosmology · Physics 2024-05-21 Hiroaki W. H. Tahara , Kazufumi Takahashi , Masato Minamitsuji , Hayato Motohashi

Conformal Weyl Gravity (CWG) predicts galactic rotation curves without invoking dark matter. This makes CWG an interesting candidate theory as an alternative to GR. This removal of the necessity of dark matter arises because the exact…

General Relativity and Quantum Cosmology · Physics 2014-04-01 Deandra Cutajar , Kristian Zarb Adami

We analyze gravitational theories with quadratic curvature terms, including the case of conformally invariant Weyl gravity, motivated by the intention to find a renormalizable theory of gravity in the ultraviolet region, yet yielding…

High Energy Physics - Theory · Physics 2014-06-18 Josef Klusoň , Markku Oksanen , Anca Tureanu

We investigate the possibility that the observed behavior of test particles outside galaxies, which is usually explained by assuming the existence of dark matter, is the result of the dynamical evolution of particles in a Weyl type…

General Relativity and Quantum Cosmology · Physics 2024-11-18 Piyabut Burikham , Tiberiu Harko , Kulapant Pimsamarn , Shahab Shahidi

When the full connection of Weyl conformal gravity is varied instead of just the metric, the resulting vacuum field equations reduce to the vacuum Einstein equation, up to the choice of local units, if and only if the torsion vanishes. This…

General Relativity and Quantum Cosmology · Physics 2014-07-30 James T. Wheeler