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Related papers: Quantum Raychaudhuri equation

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We address the validity of the formalism and results presented in [ S. Das, Phys. Rev. {\bf D89} 084068 (2014)] with regard to quantum Raychaudhuri equation. The author obtained the so called quantum Raychaudhuri equation by replacing…

General Relativity and Quantum Cosmology · Physics 2017-04-05 E. I. Lashin , Djamel Dou

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

In this review, we provide a concrete overview of the Raychaudhuri equation, Focusing theorem and Convergence conditions in a plethora of backgrounds and discuss the consequences. We also present various classical and quantum approaches…

General Relativity and Quantum Cosmology · Physics 2024-02-29 Subenoy Chakraborty , Madhukrishna Chakraborty

One of the important and famous topics in general theory of relativity and gravitation is the problem of geodesic deviation and its related singularity theorems. An interesting subject is the investigation of these concepts when quantum…

General Relativity and Quantum Cosmology · Physics 2018-02-28 Faramarz Rahmani , Mehdi Golshani

The present work deals with the Raychaudhuri equation (RE) to examine the space-time singularity both from classical and quantum point of view. The RE has been looked upon in terms of a classical linear Harmonic oscillator and Focusing…

General Relativity and Quantum Cosmology · Physics 2024-09-24 Madhukrishna Chakraborty , Subenoy Chakraborty

The classical Raychaudhuri equation predicts the formation of conjugate points for a congruence of geodesics, in a finite proper time. This in conjunction with the Hawking-Penrose singularity theorems predicts the incompleteness of…

General Relativity and Quantum Cosmology · Physics 2021-09-16 Keagan Blanchette , Saurya Das , Saeed Rastgoo

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 examine in detail the cosmology based on quantal (Bohmian) trajectories as suggested in a recent study arXiv:1404.3093[gr-qc]. We disagree with the conclusions regarding predicting the value of the cosmological constant $\Lambda$ and…

General Relativity and Quantum Cosmology · Physics 2016-03-15 E. I. Lashin

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

A recent attempt to arrive at a quantum version of Raychaudhuri's equation is looked at critically. It is shown that the method, and even the idea, has some inherent problems. The issues are pointed out here. We have also shown that it is…

General Relativity and Quantum Cosmology · Physics 2021-10-19 Shibendu Gupta Choudhury , Ananda Dasgupta , Narayan Banerjee

We investigate the geodesic deviation equation in the context of quantum improved spacetimes. The improved Raychaudhuri equation is derived, and it is shown that the classical strong energy condition does not necessarily lead to the…

General Relativity and Quantum Cosmology · Physics 2020-03-11 R. Moti , A. Shojai

The Raychaudhuri equation for a geodesic congruence in the presence of a zero-point length has been investigated. This is directly related to the small-scale structure of spacetime and possibly captures some quantum gravity effects. The…

General Relativity and Quantum Cosmology · Physics 2019-09-04 Sumanta Chakraborty , Dawood Kothawala , Alessandro Pesci

It was shown recently that replacing classical geodesics with quantal (Bohmian) trajectories gives rise to a quantum corrected Raychaudhuri equation (QRE). In this article we derive the second order Friedmann equations from the QRE, and…

General Relativity and Quantum Cosmology · Physics 2015-01-16 Ahmed Farag Ali , Saurya Das

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

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

In this work, we investigate black hole (BH) physics in the context of quantum corrections. These quantum corrections were introduced recently by replacing classical geodesics with quantal (Bohmian) trajectories and hence form a quantum…

General Relativity and Quantum Cosmology · Physics 2016-11-04 Ahmed Farag Ali , Mohammed M. Khalil

We study the classical and quantum theory of spherically symmetric spacetimes with scalar field coupling in general relativity. We utilise the canonical formalism of geometrodynamics adapted to the Painleve-Gullstrand coordinates, and…

General Relativity and Quantum Cosmology · Physics 2010-11-19 Viqar Husain , Oliver Winkler

Singularities in general relativity such as the big bang and big crunch, and exotic singularities such as the big rip are the boundaries of the classical spacetimes. These events are marked by a divergence in the curvature invariants and…

General Relativity and Quantum Cosmology · Physics 2015-10-01 Parampreet Singh

In this work we present a derivation of modified Raychaudhuri and Friedmann equations from a phenomenological model of quantum gravity based on the thermodynamics of spacetime. Starting from general gravitational equations of motion which…

General Relativity and Quantum Cosmology · Physics 2023-09-13 Ana Alonso-Serrano , Marek Liška , Antonio Vicente-Becerril

In General Relativity, gravity is universally attractive, a feature embodied by the Raychaudhuri equation which requires that the expansion of a congruence of geodesics is always non-increasing, as long as matter obeys the strong or weak…

General Relativity and Quantum Cosmology · Physics 2018-07-09 Daniel J Burger , Saurya Das , S. Shajidul Haque , Nathan Moynihan , Bret Underwood
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