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Related papers: Some generalizations of the Raychaudhuri equation

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This paper surveys aspects of the convergence and degeneration of Riemannian metrics on a given manifold M - the Cheeger-Gromov theory - and extensions thereof to Ricci curvature in place of full curvature. This theory is then applied to…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Michael T. Anderson

Usually, in mechanics, we obtain the trajectory of a particle in a given force field by solving Newton's second law with chosen initial conditions. In contrast, through our work here, we first demonstrate how one may analyse the behaviour…

General Relativity and Quantum Cosmology · Physics 2022-05-20 Rajendra Prasad Bhatt , Anushree Roy , Sayan Kar

We prove the equivalence between the several notions of generalized Ricci curvature found in the literature. As an application, we characterize when the total generalized Ricci tensor is symmetric.

Differential Geometry · Mathematics 2025-05-14 Gil R. Cavalcanti , Jaime Pedregal , Roberto Rubio

We derive loop quantum gravity corrections to the Raychaudhuri equation in the interior of a Schwarzschild black hole and near the classical singularity. We show that the resulting effective equation implies defocusing of geodesics due to…

General Relativity and Quantum Cosmology · Physics 2021-04-28 Keagan Blanchette , Saurya Das , Samantha Hergott , Saeed Rastgoo

The Raychaudhuri equation for a congruence of curves in a general non-Riemannian geometry is derived. A formal connection is established between the expansion scalar and the cross-sectional volume of the congruence. It is found that the…

General Relativity and Quantum Cosmology · Physics 2024-06-18 Anish Agashe

The n-time generalization of the Tangherlini solution [1] is considered. The equations of geodesics for the metric are integrated. For $n = 2$ it is shown that the naked singularity is absent only for two sets of parameters, corresponding…

General Relativity and Quantum Cosmology · Physics 2010-04-06 Vladimir D. Ivashchuk , Vitaly N. Melnikov

The effects on Raychaudhuri's equation of an intrinsically-discrete or particle nature of spacetime are investigated. This is done through the consideration of null congruences emerging from, or converging to, a generic point of spacetime,…

General Relativity and Quantum Cosmology · Physics 2022-10-12 Alessandro Pesci

The theory of evolution equations has been applied in various ways in general relativity. Following some general considerations about this, some illustrative examples of the use of ordinary differential equations in general relativity are…

General Relativity and Quantum Cosmology · Physics 2017-08-23 Alan D. Rendall

A quaternionic partial differential equation is shown to be a generalisation of the Riccati ordinary differential equation and its relationship with the Schrodinger equation is established. Various approaches to the problem of finding…

Mathematical Physics · Physics 2009-01-24 Viktor Kravchenko , Vladislav Kravchenko , Benjamin Williams

The paper deals with a suitable transformation related to the metric scalar of the hyper-surface so that the Raychaudhuri Equation (RE) can be written as a second order nonlinear differential equation. A first integral of this second order…

General Relativity and Quantum Cosmology · Physics 2023-06-30 Madhukrishna Chakraborty , Subenoy Chakraborty

The present work deals with the classical and quantum aspects of the Raychaudhuri equation in the framework of f(T)-gravity theory. In the background of homogeneous and isotropic Friedmann Lemaitre Robertson Walker space time, the…

General Relativity and Quantum Cosmology · Physics 2023-08-02 Madhukrishna Chakraborty , Subenoy Chakraborty

As is known from studies of gravity models in the Palatini formalism, there exist two inequivalent definitions of the generalized Ricci tensor in terms of the generalized curvature namely, $\widetilde{R}_{\mu\nu}=R^\rho_{\mu\rho\nu}$ and…

General Relativity and Quantum Cosmology · Physics 2021-10-14 Juliana Osorio Morales , Osvaldo Santillán

We study the accelerated expansion of the Universe through its consequences on a congruence of geodesics. We make use of the Raychaudhuri equation which describes the evolution of the expansion rate for a congruence of timelike or null…

General Relativity and Quantum Cosmology · Physics 2013-01-09 F. D. Albareti , J. A. R. Cembranos , A. de la Cruz-Dombriz

The generalised Raychaudhuri equations derived by Capovilla and Guven are exclusively for extremal, timelike Nambu--Goto membranes. In this article, we construct the corresponding equations for string world--sheets in the presence of a…

High Energy Physics - Theory · Physics 2009-10-30 Sayan Kar

In this paper we derive the generalisations of Gauss-Codazzi, Raychaudhuri and area change equations for classical relativistic branes and multidimensional fluids in arbitrary background manifolds with metricity and torsion. The kinematical…

High Energy Physics - Theory · Physics 2009-10-30 E. Zafiris

We develop the theory of weighted Ricci curvature in a weighted Lorentz-Finsler framework and extend the classical singularity theorems of general relativity. In order to reach this result, we generalize the Jacobi, Riccati and Raychaudhuri…

Differential Geometry · Mathematics 2021-07-28 Yufeng Lu , Ettore Minguzzi , Shin-ichi Ohta

In Riemannian geometry, the Ricci flow is the analogue of heat diffusion; a deformation of the metric tensor driven by its Ricci curvature. As a step towards resolving the problem of time in quantum gravity, we attempt to merge the Ricci…

General Relativity and Quantum Cosmology · Physics 2022-09-05 Mohammed Alzain

The geodesic deviation equation, describing the relative accelerations of nearby particles, and the Raychaudhury equation, giving the evolution of the kinematical quantities associated with deformations (expansion, shear and rotation) are…

General Relativity and Quantum Cosmology · Physics 2012-12-20 Tiberiu Harko , Francisco S. N. Lobo

The Raychaudhuri equation and its consequences for chronality are studied in the context of Finsler spacetimes. It is proved that the notable singularity theorems of Lorentzian geometry extend to the Finslerian domain. Indeed, so do the…

General Relativity and Quantum Cosmology · Physics 2015-09-25 E. Minguzzi

In this paper we review the extent to which one can use classical distribution theory in describing solutions of Einstein's equations. We show that there are a number of physically interesting cases which cannot be treated using…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Roland Steinbauer , James A. Vickers