English
Related papers

Related papers: Naked Singularity Formation In f(R) Gravity

200 papers

We explore a collapsing cosmology driven by a scalar field which is minimally coupled to gravity in a spatially at and spherically symmetric, isotropic and homogeneous space-time, with a variable timescale that avoids the final singularity.…

General Relativity and Quantum Cosmology · Physics 2021-05-07 Jaime M. Hernandez , Mauricio Bellini , Claudia Moreno

Dynamical analysis of spherically symmetric collapsing star surrounding in locally anisotropic environment with expansion-free condition is presented in $f(R,T)$ gravity, where $R$ corresponds to Ricci scalar and $T$ stands for the trace of…

General Relativity and Quantum Cosmology · Physics 2015-04-21 Ifra Noureen , M. Zubair

We present here an overview of our basic understanding and recent developments on spacetime singularities in the Einstein theory of gravity. Several issues related to physical significance and implications of singularities are discussed.…

General Relativity and Quantum Cosmology · Physics 2015-06-17 Pankaj S. Joshi

We study the linearised stability of the nakedly singular negative mass Schwarzschild solution against gravitational perturbations. There is a one parameter family of possible boundary conditions at the singularity. We give a precise…

High Energy Physics - Theory · Physics 2009-10-07 Gary W. Gibbons , Sean A. Hartnoll , Akihiro Ishibashi

We investigate the unhindered gravitational collapse of a homogeneous scalar field with nonzero potential, a two-dimensional analog of the Mexican hat-shaped Higgs field potential. The collapsing scalar field is surrounded by an exterior…

General Relativity and Quantum Cosmology · Physics 2022-04-01 Karim Mosani , Dipanjan Dey , Kaushik Bhattacharya , Pankaj S. Joshi

The paper deals with collapse dynamics of a spherically symmetric massive star in the framework of non-equilibrium themodynamic prescription through particle creation mechanism. The matter content in the star is in the form of perfect uid…

General Relativity and Quantum Cosmology · Physics 2021-01-26 Sudipto Bhattacharjee , Subhajit Saha , Subenoy Chakraborty

We investigate here quantum effects in gravitational collapse of a scalar field model which classically leads to a naked singularity. We show that non-perturbative semi-classical modifications near the singularity, based on loop quantum…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Rituparno Goswami , Pankaj S. Joshi , Parampreet Singh

The gravitational collapse of a spherical distribution, in a class of f(R) theories of gravity, where f(R) is power function of R, is discussed. The spacetime is assumed to admit a homothetic Killing vector. In the collapsing modes, some of…

General Relativity and Quantum Cosmology · Physics 2016-07-28 Soumya Chakrabarti , Narayan Banerjee

The gravitational strength of the central singularity in spherically symmetric space-times is investigated. Necessary conditions for the singularity to be gravitationally weak are derived and it is shown that these are violated in a wide…

General Relativity and Quantum Cosmology · Physics 2010-11-19 Brien C. Nolan

This article gives an elementary overview of the end-state of gravitational collapse according to classical general relativity. The focus of discussion is the formation of black holes and naked singularities in various physically reasonable…

General Relativity and Quantum Cosmology · Physics 2007-05-23 T. P. Singh

The hypothesis of cosmic censorship plays a crucial role in classical general relativity, namely, to ensure that naked singularities would never occur from the black hole singularity. In this paper, we will present how energy conditions…

General Relativity and Quantum Cosmology · Physics 2021-12-24 Javad T. Firouzjaee

We study five dimensional(5D) spherically symmetric self-similar perfect fluid space-time with adiabatic equation of state, considering all the families of future directed non-spacelike geodesics. The space-time admits globally strong…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Sanjay B. Sarwe , R. V. Saraykar

The present work investigates the gravitational collapse of a perfect fluid in $f(R)$ gravity models. For a general $f(R)$ theory, it is shown analytically that a collapse is quite possible. The singularity formed as a result of the…

General Relativity and Quantum Cosmology · Physics 2016-03-30 Soumya Chakrabarti , Narayan Banerjee

We have studied the images of the Brans-Dicke-Kerr spacetime with a dimensionless Brans-Dicke parameter $\omega$, which belongs to axisymmetric rotating solutions in the Brans-Dicke theory. Our results show that the Brans-Dicke-Kerr…

General Relativity and Quantum Cosmology · Physics 2025-12-18 Fen Long , Weike Deng , Xin Qin , Songbai Chen , Jiliang Jing

Charged stars have the potential of becoming charged black holes or even naked singularities. It is presented a set of numerical solutions of the Tolman-Oppenheimer-Volkov equations that represents spherical charged compact stars in…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Cristian R. Ghezzi

In order to study the gravitational collapse of charged matter we analyze the simple model of an self-gravitating massless scalar field coupled to the electromagnetic field in spherical symmetry. The evolution equations for the…

General Relativity and Quantum Cosmology · Physics 2014-11-07 Jose M. Torres , Miguel Alcubierre

We study the cosmology of canonically normalized scalar fields that lead to an equation of state parameter of w_\phi=p_\phi/\rho_\phi<-1 without violating the weak energy condition: rho=\Sigma_i\rho_i \geq 0 and \rho_i+p_i\geq 0. This kind…

Astrophysics · Physics 2007-05-23 A. de la Macorra , G. German

We use 1-dimensional numerical simulations to study spherical collapse in the f(R) gravity models. We include the nonlinear coupling of the gravitational potential to the scalar field in the theory and use a relaxation scheme to follow the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Alex Borisov , Bhuvnesh Jain , Pengjie Zhang

We compare the gravitational collapse of homogeneous perfect fluid with various equations of state in the framework of General Relativity and in $R^2$ gravity. We make our calculations using dimensionless time with characteristic timescale…

General Relativity and Quantum Cosmology · Physics 2019-03-27 Artyom V. Astashenok , Karim Mosani , Sergey D. Odintsov , Gauranga C. Samanta

This paper deals with the cancellation mechanism, which identifies the energy density of space-time expansion in an empty universe with the zero-point energy density and avoids the scale discrepancy with the observed energy density…

General Physics · Physics 2018-06-12 Christian Henke