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Related papers: A note on wormholes as compact stellar objects

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We consider a configuration consisting of a wormhole filled by a perfect fluid. Such a model can be applied to describe stars as well as neutron stars with a nontrivial topology. The presence of a tunnel allows for motion of the fluid,…

Astrophysics of Galaxies · Physics 2015-05-27 V. Dzhunushaliev , V. Folomeev , B. Kleihaus , J. Kunz

Recently, spherically symmetric, static wormholes supported by exotic dust and a radial magnetic field have been derived and argued to be stable with respect to linear radial fluctuations. In this report we point out that these wormholes…

General Relativity and Quantum Cosmology · Physics 2010-04-06 Olivier Sarbach , Thomas Zannias

Wormholes are outstanding solutions of Einstein's General Relativity. They were worked out in the late 1980's by Morris and Thorne, who have figured out a recipe that wormholes must obey in order to be traversable, that is, safely crossed…

General Relativity and Quantum Cosmology · Physics 2023-03-29 A. S. Agrawal , B. Mishra , P. H. R. S. Moraes

The study of traversable wormholes is very hot topic for the past 30 years. One of the best possible way to make traversable wormhole is using the thin-shells to cut and paste two spacetime which has tunnel from one region of space-time to…

General Relativity and Quantum Cosmology · Physics 2016-10-27 Ali Övgün

This paper generalizes two of the author's earlier wormhole solutions that are characterized by an extra spatial dimension. This paper adds the assumption that the components of the line element are functions not only of the radial…

General Relativity and Quantum Cosmology · Physics 2025-06-17 Peter K. F. Kuhfittig

The quartic self-interacting conformal scalar field is used to construct a thin-shell wormhole satisfying all energy conditions. Accompanying the scalar field is the extremal Reissner-Nordstr\"om black hole with a positive cosmological…

General Relativity and Quantum Cosmology · Physics 2020-03-31 S. Danial Forghani , S. Habib Mazharimousavi , Mustafa Halilsoy

It is shown that the existence of static, cylindrically symmetric wormholes does not require violation of the weak or null energy conditions near the throat, and cylindrically symmetric wormhole geometries can appear with less exotic…

General Relativity and Quantum Cosmology · Physics 2009-07-30 Kirill A. Bronnikov , José P. S. Lemos

Static, spherically symmetric, traversable wormholes, induced by massless, nonminimally coupled scalar fields in general relativity, are shown to be unstable under spherically symmetric perturbations. The instability is related to…

General Relativity and Quantum Cosmology · Physics 2007-05-23 K. A. Bronnikov , S. Grinyok

Although wormholes can be treated as topological objects in spacetime and from a global point-of-view, a precise definition of what a wormhole throat is and where it can be located can be developed and treated entirely in terms of local…

General Relativity and Quantum Cosmology · Physics 2007-05-23 David Hochberg , Matt Visser

Morris-Thorne wormholes with a cosmological constant \Lambda have been studied extensively, even allowing \Lambda to be replaced by a space variable scalar. These wormholes cannot exist, however, if \Lambda is both space and time dependent.…

General Relativity and Quantum Cosmology · Physics 2011-12-21 Peter K. F. Kuhfittig

In this work we wonder if there is a way to generate a wormhole (WH) in nature using "normal" matter. In order to give a first answer to this question, we study a massless scalar field coupled to an electromagnetic one (dilatonic field)…

General Relativity and Quantum Cosmology · Physics 2021-02-09 Tonatiuh Matos , Galaxia Miranda

Wormhole geometries in curvature-matter coupled modified gravity are explored, by considering an explicit nonminimal coupling between an arbitrary function of the scalar curvature, R, and the Lagrangian density of matter. It is the…

General Relativity and Quantum Cosmology · Physics 2010-11-09 Nadiezhda Montelongo Garcia , Francisco S. N. Lobo

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 review a new traversable-wormhole solution of the gravitational field equation of general relativity without exotic matter. Instead of having exotic matter to keep the wormhole throat open, the solution relies on a 3-dimensional…

General Relativity and Quantum Cosmology · Physics 2023-07-25 Frans R. Klinkhamer

We consider the hypothesis that some active galactic nuclei and other compact astrophysical objects may be current or former entrances to wormholes. A broad mass spectrum for astrophysical wormholes is possible. We consider various new…

Astrophysics · Physics 2008-11-26 N. S. Kardashev , I. D. Novikov , A. A. Shatskiy

This paper extends an earlier study by the author [Phys. Rev. D, vol. 98, 064041 (2018), arXiv:1809.01993] in several significant ways. To begin with, the extra spatial dimension is assumed to be time dependent, while the redshift and shape…

General Relativity and Quantum Cosmology · Physics 2023-12-06 Peter K. F. Kuhfittig

It is known that traversible wormholes require negative energy density. We here argue how much negative energy is needed for wormholes, using a local analysis which does not assume any symmetry. and in particular allows dynamic…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Daisuke Ida , Sean A. Hayward

In the context of $2+1-$dimensional gravity coupled to a particular nonlinear electrodynamics (NED), we obtain a class of traversable / Morris-Thorne type wormhole solutions. The problem is reduced to a single function dependence in which…

General Relativity and Quantum Cosmology · Physics 2017-03-17 S. Habib Mazharimousavi , Z. Amirabi , M. Halilsoy

For an arbitrary Tolman wormhole, unconstrained by symmetry, we shall define the bounce in terms of a three-dimensional edgeless achronal spacelike hypersurface of minimal volume. (Zero trace for the extrinsic curvature plus a "flare-out"…

General Relativity and Quantum Cosmology · Physics 2009-10-31 David Hochberg , Carmen Molina-Paris , Matt Visser

We formulate the traversability of wormhole throats as a local and covariant null defocusing condition derived from the Raychaudhuri equation. Since unimodular gravity preserves the local geometric structure of spacetime, the null focusing…

General Relativity and Quantum Cosmology · Physics 2026-02-03 Erick Pastén , Marco Bosquez , Norman Cruz