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Related papers: Gravitationally collapsing stars in $f(R)$ gravity

200 papers

In this paper, we study the dynamics of shearfree dissipative gravitational collapse in modified Gauss-Bonnet theory of gravity - so called f(G) gravity. The field equations of f(G) gravity are applied to shearfree spherical interior…

General Relativity and Quantum Cosmology · Physics 2015-06-12 M. Sharif , G. Abbas

We analyze spherical dust collapse with non-vanishing radial pressure, $\Pi$, and vanishing tangential stresses. Considering a barotropic equation of state, $\Pi=\gamma\rho$, we obtain an analytical solution in closed form---which is exact…

General Relativity and Quantum Cosmology · Physics 2010-05-12 Sergio M. C. V. Goncalves , Sanjay Jhingan

We study gravitational collapse of a spherical fluid in nonrelativistic general covariant theory of the Ho\v{r}ava-Lifshitz gravity with the projectability condition and an arbitrary coupling constant $\lambda$, where $|\lambda - 1|$…

High Energy Physics - Theory · Physics 2015-06-01 Jared Greenwald , Jonatan Lenells , V. H. Satheeshkumar , Anzhong Wang

The curvature singularity in viable f(R) gravity models is examined when the background density is dense. This singularity could be eliminated by adding the $R^{2}$ term in the Lagrangian. Some of cosmological consequences, in particular…

Cosmology and Nongalactic Astrophysics · Physics 2012-09-03 Chung-Chi Lee , Chao-Qiang Geng , Louis Yang

We investigate the rotational core collapse of a rapidly rotating relativistic star by means of a 3+1 hydrodynamical simulations in conformally flat spacetime of general relativity. We concentrate our investigation to the bounce of the…

Astrophysics · Physics 2007-05-23 Motoyuki Saijo

It is argued in the literature that gravity is an emergent phenomenon and is a statistical tendency for a gravitational system to attain the maximal entropy state which maintains the holographic principle. In this paper, we show that…

General Relativity and Quantum Cosmology · Physics 2014-01-08 Qiao-Jun Cao

We model the behaviour of a relativistic spherically symmetric shearing fluid undergoing gravitational collapse with heat flux. It is demonstrated that the governing equation for the gravitational behaviour is a Riccati equation. We show…

General Relativity and Quantum Cosmology · Physics 2008-11-26 S. S. Rajah , S. D. Maharaj

Rotating relativistic stars have been studied extensively in recent years, both theoretically and observationally, because of the information one could obtain about the equation of state of matter at extremely high densities and because…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Nikolaos Stergioulas

We analyze the evolution of a homogenous and pressureless ball of dust (or "star") in ghost-free massive gravity on de Sitter spacetime. We find that gravitational collapse does not take place for all parameters of the massive gravity…

High Energy Physics - Theory · Physics 2021-09-23 Roman Berens , Luke Krauth , Rachel A. Rosen

We discuss the occurrence of gravitational phase transitions and instabilities in a gas of self-gravitating fermions within the framework of general relativity. In the classical (nondegenerate) limit, the system undergoes a gravitational…

General Relativity and Quantum Cosmology · Physics 2020-02-11 Pierre-Henri Chavanis , Giuseppe Alberti

We consider here the structure of rotating compact objects endowed with a magnetic field in general relativity as models of pulsars. We discuss first the structure of rotating stars in the framework of Hartle taking different realistic…

Astrophysics · Physics 2014-10-13 Anshu Gupta , Amruta Mishra , Hiranmaya Mishra , A. R. Prasanna

We study the fate of gravitational collapse in presence of a cosmological constant. The junctions conditions between static and non-static space-times are deduced. Three apparent horizon are formed, but only two have physical significance,…

General Relativity and Quantum Cosmology · Physics 2007-05-23 M. Cissoko , J. C. Fabris , J. Gariel , G. Le Denmat , N. O. Santos

We consider the end state of collapsing null radiation with a string fluid. It is shown that, if diffusive transport is assumed for the string, that a naked singularity can form (at least locally). The model has the advantage of not being…

General Relativity and Quantum Cosmology · Physics 2009-11-10 K S Govinder , M Govender

We review black hole solutions and self-gravitating structures in f(R)-gravity.

General Relativity and Quantum Cosmology · Physics 2012-02-06 M. De Laurentis , S. Capozziello

We investigate the behaviour of a relativistic spherically symmetric radiative star with an accelerating, expanding and shearing interior matter distribution in the presence of anisotropic pressures. The junction condition can be written in…

General Relativity and Quantum Cosmology · Physics 2015-06-12 S. Thirukkanesh , S. S. Rajah , S. D. Maharaj

It is now a well established fact based on several observations that we live in a Universe dominated by dark energy. The most natural candidates for dark energy are fields in curved space-time. We develop the formalism to study the…

High Energy Physics - Phenomenology · Physics 2010-07-30 Anupam Singh

We perform linear analysis of thermal instability in a contracting large cloud filled with warm HI gas and investigate the effect of metallicity and radiation flux. When the cloud reaches critical density n_f, the cloud fragments into cool,…

Astrophysics · Physics 2009-10-31 Motomichi Tashiro , Ryoichi Nishi

Dynamical behavior and future singularities of $f(R, T,R_{\mu\nu}T^{\mu\nu})$ gravitational theory are investigated. This gravitational model is a more complete form of the $f(R,T)$ gravity which can offer new dynamics for the universe. We…

General Relativity and Quantum Cosmology · Physics 2020-04-06 Maryam Aghaei Abchouyeh , Behrouz Mirza , Parisa Shahidi , Fatemeh Oboudiat

The collapse of massive rotating stellar cores and the associated accretion onto the newborn compact object is thought to power long gamma ray bursts (GRBs). The physical scale and dynamics of the accretion disk are initially set by the…

High Energy Astrophysical Phenomena · Physics 2015-06-16 Aldo Batta , William H. Lee

Here $f(R)$-cosmology is discussed using a different approach. This model explains early-inflation, emergence of cosmic background radiation at the exit from inflation, cosmic deceleration during radiation-dominance followed by deceleration…

General Relativity and Quantum Cosmology · Physics 2008-10-09 S. K. Srivastava