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Related papers: A Star Harbouring a Wormhole at its Core

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This paper presents a new wormhole solution by assuming that a homogeneously distributed fluid with equation of state $p=\omega\rho$ can be adapted to an anisotropic spacetime such as a wormhole and that this spacetime admits a…

General Relativity and Quantum Cosmology · Physics 2017-07-14 Peter K. F. Kuhfittig

We analyze the stress-energy tensor necessary to generate a general stationary and axisymmetric spacetime. The constraints on the geometry arising from considering a perfect fluid as a source are derived. For a fluid with a nonzero stress…

General Relativity and Quantum Cosmology · Physics 2007-05-23 S. E. Perez Bergliaffa , K. E. Hibberd

We investigate the stability of the wormhole of the Mors-Thorne-Ellis-Bronnikov type. In our model the matter inside it consists of a radial magnetic field and an ideal phantom-fluid. Properties of the matter are described in section 1, 2…

General Relativity and Quantum Cosmology · Physics 2012-04-10 Igor Novikov , Alexander Shatskiy

This paper extends several previous studies of wormholes supported by two non-interacting fluids beginning with a combined model of ordinary matter and phantom dark energy with an anisotropic matter distribution. After noting that such…

General Relativity and Quantum Cosmology · Physics 2023-05-02 Peter K. F. Kuhfittig

I derive a system of pulsation equations for compact stars made up of an arbitrary number of perfect fluids that can be used to study radial oscillations and stability with respect to small perturbations. I assume spherical symmetry and…

General Relativity and Quantum Cosmology · Physics 2020-07-15 Ben Kain

An exact solution of the Einstein field equations given the barotropic equation of state $p=\omega\rho$ yields two possible models: (1) if $\omega <-1$, we obtain the most general possible anisotropic model for wormholes supported by…

General Relativity and Quantum Cosmology · Physics 2016-06-29 Peter K. F. Kuhfittig

A static, spherically symmetric spacetime with negative pressures is conjectured inside a star. The gravitational field is repulsive and so a central singularity is avoided. The positive energy density and the pressures of the imperfect…

General Relativity and Quantum Cosmology · Physics 2020-05-05 Hristu Culetu

We investigate relativistic spherically symmetric static perfect fluid models in the framework of the theory of dynamical systems. The field equations are recast into a regular dynamical system on a 3-dimensional compact state space,…

General Relativity and Quantum Cosmology · Physics 2009-11-10 J. Mark Heinzle , N. Rohr , C. Uggla

We have found a simple exact solution of spherically-symmetrical Einstein equations describing a wormhole for an inhomogeneous distribution of the phantom energy. The equation of state is linear but highly anisotropic: while the radial…

General Relativity and Quantum Cosmology · Physics 2009-11-11 O. B. Zaslavskii

We analize the stability of a class of thin-shell wormholes with spherical symmetry evolving in flat FRW spacetimes. The wormholes considered here are supported at the throat by a perfect fluid with equation of state $\mathcal{P}=w\sigma$…

General Relativity and Quantum Cosmology · Physics 2011-05-12 M. La Camera

We consider stationary, cylindrically symmetric configurations in general relativity and formulate necessary conditions for the existence of rotating cylindrical wormholes. It is shown that in a comoving reference frame the rotational part…

General Relativity and Quantum Cosmology · Physics 2013-09-12 Kirill A. Bronnikov , Vladimir G. Krechet , José P. S. Lemos

We model a rotating star as a compressible fluid subject to gravitational forces. In almost all the mathematical literature the entropy is considered to be constant. Here we allow it to be variable. We consider a star that steadily rotates…

Analysis of PDEs · Mathematics 2022-04-19 Juhi Jang , Walter A. Strauss , Yilun Wu

This paper investigates the geometry of static traversable wormhole through Noether symmetry approach in $f(R)$ gravity. We take perfect fluid distribution and formulate symmetry generators with associated conserved quantities corresponding…

General Relativity and Quantum Cosmology · Physics 2018-04-04 M. Sharif , Iqra Nawazish

We describe recent progress in the numerical study of the structure of rapidly rotating superfluid neutron star models in full general relativity. The superfluid neutron star is described by a model of two interpenetrating and interacting…

General Relativity and Quantum Cosmology · Physics 2007-05-23 R. Prix , J. Novak , G. L. Comer

In this article, we assume that a cold charged perfect fluid is constructing a spherical relativistic star. Our purpose is the investigation of the dynamical properties of its exterior geometry, through simulating the geodesic motion of a…

General Relativity and Quantum Cosmology · Physics 2015-03-19 Mohsen Fathi

We study the stability and the scattering properties of a spacetime with a topological defect along a spherical bubble. This bubble connects two flat spacetimes which are asymptotically Minkowski, so that the resulting universe may be…

General Relativity and Quantum Cosmology · Physics 2016-05-09 J. P. M. Pitelli , R. A. Mosna

We study the geometry of a wormhole spacetime filled with anisotropic matter in the context of general relativity. In the course of the study, new static and spherically symmetric solutions, analytic and numerical ones, are found. We…

General Relativity and Quantum Cosmology · Physics 2019-09-04 Hyeong-Chan Kim , Youngone Lee

We develop a general formalism to treat, in general relativity, the linear oscillations of a two-fluid star about static (non-rotating) configurations. Such a formalism is intended for neutron stars, whose matter content can be described,…

General Relativity and Quantum Cosmology · Physics 2009-10-31 G. L. Comer , David Langlois , Lap Ming Lin

Given an anisotropic fluid source, we determine in closed forms, upon solving the field equations of general relativity (GR) and teleparallel gravity (TEGR) coupled to a cosmological constant, cylindrically symmetric four-dimensional…

General Relativity and Quantum Cosmology · Physics 2021-03-17 Mustapha Azreg-Aïnou

In this article, we provide a pedagogical review of the Tolman-Oppenheimer-Volkoff (TOV) equation and its solutions which describe static, spherically symmetric gaseous stars in general relativity. Our discussion starts with a systematic…

General Relativity and Quantum Cosmology · Physics 2021-06-15 Emmanuel Chavez Nambo , Olivier Sarbach