English
Related papers

Related papers: Congruence Kinematics in Conformal Gravity

200 papers

We study the evolution of time-like congruences in the vacuum solutions of Weyl conformal theory of gravity. Using the Raycaudhuri equation, we show that for positive values of the coeffcient of the linear term in the solution and in the…

General Relativity and Quantum Cosmology · Physics 2016-02-03 Morteza Mohseni , Mohsen Fathi

We consider a timelike geodesic congruence in the presence of perturbative quantum fluctuations of the spacetime metric. We calculate the change in the volume of a bundle of geodesics due to such fluctuations and thereby obtain a…

General Relativity and Quantum Cosmology · Physics 2023-05-29 Sang-Eon Bak , Maulik Parikh , Sudipta Sarkar , Francesco Setti

We present a scale-invariant theory, conformal gravity, which closely resembles the geometrodynamical formulation of general relativity (GR). While previous attempts to create scale-invariant theories of gravity have been based on Weyl's…

General Relativity and Quantum Cosmology · Physics 2017-08-23 Edward Anderson , Julian Barbour , Brendan Foster , Niall O'Murchadha

We study Weyl conformal geometry as a general gauge theory of the Weyl group (of Poincar\'e and dilatations symmetries) in a manifestly Weyl gauge covariant formalism in which this geometry is automatically metric and physically relevant.…

High Energy Physics - Theory · Physics 2025-03-31 C. Condeescu , D. M. Ghilencea , A. Micu

We present an alternative cosmology based on conformal gravity, as originally introduced by H. Weyl and recently revisited by P. Mannheim and D. Kazanas. Unlike past similar attempts our approach is a purely kinematical application of the…

General Relativity and Quantum Cosmology · Physics 2010-04-30 Gabriele U. Varieschi

We review recent developments in physical implications of Weyl conformal geometry. The associated Weyl quadratic gravity action is a gauge theory of the Weyl group of dilatations and Poincar\'e symmetry. Weyl conformal geometry is defined…

High Energy Physics - Theory · Physics 2025-06-05 D. M. Ghilencea

We provide a gauge-invariant theory of gravitation in the context of Weyl Integrable Space-Times. After making a brief review of the theory's postulates, we carefully define the observers' proper-time and point out its relation with…

General Relativity and Quantum Cosmology · Physics 2014-10-31 F. P. Poulis , J. M. Salim

The Bach equation, i.e., the vacuum field equation following from the Lagrangian L=C_{ijkl}C^{ijkl}, will be completely solved for the case that the metric is conformally related to the cartesian product of two 2-spaces; this covers the…

General Relativity and Quantum Cosmology · Physics 2009-10-31 V. Dzhunushaliev , H. -J. Schmidt

Despite the fact that General Relativity (GR) has been very successful, many alternative theories of gravity have attracted the attention of a significant number of theoretical physicists. Among these theories, we have theories with…

General Relativity and Quantum Cosmology · Physics 2019-05-14 J. B. Formiga

A short survey of some material related to conformal general relativity (CGR), integrable Weyl geometry, and Dirac-Weyl (DW) theory is given which suggests that CGR is essentially equivalent to DW with quantum mass equivalent to conformal…

General Relativity and Quantum Cosmology · Physics 2008-01-03 Robert Carroll

We present the exact time-dependent solutions on inhomogeneous spherically symmetric space-time in the conformal invariant Weyl gravity. For this purpose, the subclass of the Lemaitre-Tolman metric which is supported by an anisotropic fluid…

General Relativity and Quantum Cosmology · Physics 2023-12-14 Malihe Heydari-Fard , Mohammad Rahim Bordbar , Golnaz Mohammadi

We give new solutions of the quantum conformal deformations of the full Maxwell equations in terms of deformations of the plane wave. We study the compatibility of these solutions with the conservation of the current. We also start the…

Quantum Algebra · Mathematics 2009-11-10 V. K. Dobrev , S. T. Petrov

In a given geometry, the kinematics of a congruence of curves is described by a set of three quantities called expansion, rotation, and shear. The equations governing the evolution of these quantities are referred to as kinematic equations.…

General Relativity and Quantum Cosmology · Physics 2023-09-12 Anish Agashe

In the present paper we give conclusive arguments pointing at physical equivalence among conformally related metrics. Based on the argument that any consistent effective theory of spacetime must be invariant under the one-parameter group of…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Israel Quiros , Rolando Cardenas , Rolando Bonal

We discuss the concepts of Weyl and Riemann frames in the context of metric theories of gravity and state the fact that they are completely equivalent as far as geodesic motion is concerned. We apply this result to conformally flat…

General Relativity and Quantum Cosmology · Physics 2015-05-27 C. Romero , J. B. Fonseca-Neto , M. L. Pucheu

We consider conformal gravity as a gauge natural theory. We study its conservation laws and superpotentials. We also consider the Mannheim and Kazanas spherically symmetric vacuum solution and discuss conserved quantities associated to…

General Relativity and Quantum Cosmology · Physics 2015-02-10 M. Campigotto , L. Fatibene

We consider a congruence of null geodesics in the presence of a quantized spacetime metric. The coupling to a quantum metric induces fluctuations in the congruence; we calculate the change in the area of a pencil of geodesics induced by…

General Relativity and Quantum Cosmology · Physics 2024-07-29 Sang-Eon Bak , Maulik Parikh , Sudipta Sarkar , Francesco Setti

The kinematical quantities derived from the velocity field of a nongeodesic congruence are studied. We found the shear tensor components are finite in time but diverge at the event horizon of the spacetime located at $\rho = 0$. The surface…

High Energy Physics - Theory · Physics 2014-10-20 Hristu Culetu

In this paper, we analyze the classical geometric flow as a dynamical system. We obtain an action for this system, such that its equation of motion is the Raychaudhuri equation. This action will be used to quantize this system. As the…

High Energy Physics - Theory · Physics 2021-03-11 Salwa Alsaleh , Lina Alasfar , Mir Faizal , Ahmed Farag Ali

We review uniqueness results for the kinematical part of loop quantum gravity. After sketching the general loop formalism, the holonomy-flux and the Weyl algebras are introduced. In both cases, then, diffeomorphism invariant representations…

Mathematical Physics · Physics 2015-07-21 Christian Fleischhack
‹ Prev 1 2 3 10 Next ›