English
Related papers

Related papers: Comment on "Quantum Raychaudhuri equation"

200 papers

We compute quantum corrections to the Raychaudhuri equation, by replacing classical geodesics with quantal (Bohmian) trajectories, and show that they prevent focusing of geodesics, and the formation of conjugate points. We discuss…

General Relativity and Quantum Cosmology · Physics 2015-06-18 Saurya Das

The above comment [E. I. Lashin, D. Dou, arXiv:1606.04738] claims that the paper "Quantum Raychaudhuri Equation" by S. Das, Phys. Rev. D89 (2014) 084068 [arXiv:1404.3093] has "problematic points" with regards to its derivation and…

General Relativity and Quantum Cosmology · Physics 2017-04-05 Saurya Das

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

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

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

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

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

I first recount Raychaudhuri's deep involvement with the singularity problem in general relativity. I then argue that precisely the same situation has arisen today in loop quantum cosmology as obtained when Raychaudhuri discovered his…

General Relativity and Quantum Cosmology · Physics 2011-05-06 Naresh Dadhich

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

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 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

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

We present a brief review on the Raychaudhuri equations. Beginning with a summary of the essential features of the original article by Raychaudhuri and subsequent work of numerous authors, we move on to a discussion of the equations in the…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Sayan Kar , Soumitra SenGupta

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 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

The works reported in this thesis primarily address the application of the Raychaudhuri equation in two intriguing problems in gravitational physics. These problems still lack universally accepted explanations. The first problem is related…

General Relativity and Quantum Cosmology · Physics 2023-01-20 Shibendu Gupta Choudhury

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

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 Raychaudhuri equation has seen extensive use in general relativity, most notably in the development of various singularity theorems. In this rather technical article we shall generalize the Raychaudhuri equation in several ways. First…

General Relativity and Quantum Cosmology · Physics 2011-05-13 Gabriel Abreu , Matt Visser
‹ Prev 1 2 3 10 Next ›