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We cut and paste two Banados-Teitelboim-Zanelli (BTZ) spacetimes at a throat by the Darmois-Israel method to construct a rotating wormhole with a thin shell filled with a barotropic fluid. The thin shell at the throat and both sides of the…

General Relativity and Quantum Cosmology · Physics 2018-08-16 Naoki Tsukamoto , Takafumi Kokubu

We consider Lorentzian wormholes with a phantom field and chiral matter fields. The chiral fields are described by the non-linear sigma model with or without a Skyrme term. When the gravitational coupling of the chiral fields is increased,…

General Relativity and Quantum Cosmology · Physics 2013-05-08 Efstathios Charalampidis , Theodora Ioannidou , Burkhard Kleihaus , Jutta Kunz

The well-known problem of wormholes in general relativity (GR) is the necessity of exotic matter, violating the Weak Energy Condition (WEC), for their support. This problem looks easier if, instead of island-like configurations, one…

General Relativity and Quantum Cosmology · Physics 2020-01-08 K. A. Bronnikov , S. V. Bolokhov , M. V. Skvortsova

The properties of an hyperbolically-expanding wormhole are studied. Using a particular equation of state for the fluid on the wormhole throat, we reached an equation of motion for the throat that leads to a constant surface energy density…

General Relativity and Quantum Cosmology · Physics 2019-06-21 Hristu Culetu

We consider static spherically symmetric wormhole configurations in a gravitational theory of a scalar field with a potential $V(\phi)$ and nonminimal derivative coupling to the curvature describing by the term $(\epsilon g_{\mu\nu} +…

General Relativity and Quantum Cosmology · Physics 2015-06-03 Sergey Sushkov , Roman Korolev

We construct thin shell wormholes in the magnetic Melvin universe. It is shown that in order to make a TSW in the Melvin spacetime the radius of the throat can not be larger than $\frac{2}{B_{0}}$ in which $B_{0}$ is the magnetic field…

General Relativity and Quantum Cosmology · Physics 2014-05-28 S. Habib Mazharimousavi , M. Halilsoy , Z. Amirabi

A thin-shell wormhole is crafted by the cut-and-paste method of two Bardeen de-Sitter black holes using Darmois-Israel formalism. Energy conditions are considered for different values of magnetic charge while both mass and cosmological…

General Relativity and Quantum Cosmology · Physics 2020-02-11 Hassan Alshal

We examine the linear stability of static, spherically symmetric wormhole solutions of Einstein's field equations coupled to a massless ghost scalar field. These solutions are parametrized by the areal radius of their throat and the product…

General Relativity and Quantum Cosmology · Physics 2008-12-25 J. A. Gonzalez , F. S. Guzman , O. Sarbach

We study wormhole geometries embedded in an expanding universe within a four-scalar non-linear $\sigma$ model, where the target-space metric is identified with the spacetime Ricci tensor. In this framework, wormholes can remain stable even…

General Relativity and Quantum Cosmology · Physics 2026-01-16 Taishi Katsuragawa , Shin'ichi Nojiri , Sergei D. Odintsov

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

When Morris and Thorne first proposed that traversable wormholes may be actual physical objects, they concentrated on the geometry by specifying the shape and redshift functions. This mathematical approach necessarily raises questins…

General Relativity and Quantum Cosmology · Physics 2015-08-11 Peter K. F. Kuhfittig

Motivated by recent proposals of possible wormhole existence in galactic halos, we analyse the cosmological evolution of wormhole solutions in modified $f(R)$ gravity. We construct a dynamical wormhole that asymptotically approaches FLRW…

General Relativity and Quantum Cosmology · Physics 2016-08-24 Sebastian Bahamonde , Mubasher Jamil , Petar Pavlovic , Marko Sossich

Some new class of Chaplygin wormholes are investigated in the framework of a Chaplygin gas with equation of state $ p = - \frac{A}{\rho}$, $A>0$. Since empty spacetime ($ p = \rho = 0 $) does not follow Chaplygin gas, so the interior…

General Relativity and Quantum Cosmology · Physics 2008-11-26 F. Rahaman , M. Kalam , K. A. Rahman

We provide a new matter source that supplies fuel to construct wormhole spacetime. The exact wormhole solutions are found in the model having, besides real matter, an anisotropic dark energy. We have shown that the exotic matters that are…

General Physics · Physics 2013-03-14 Farook Rahaman , Saibal Ray , Safiqul Islam

The purpose of this paper is to construct spherical thin-shell wormhole solutions through cut and paste technique and investigate the stability of these solutions in the vicinity of modified Chaplygin gas. The Darmois-Israel formalism is…

General Relativity and Quantum Cosmology · Physics 2013-10-02 M. Sharif , M. Azam

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

We obtain the self-interaction for a point charge in the space-time of a cylindrical thin-shell wormhole connecting two identical locally flat geometries with a constant deficit angle. Although this wormhole geometry is locally…

General Relativity and Quantum Cosmology · Physics 2015-06-11 E. Rubín de Celis , O. P. Santillán , C. Simeone

In this article we present a theoretical construction of spacetimes with a thin shell that joins two different local cosmic string geometries. We study two types of global manifolds, one representing spacetimes with a thin shell surrounding…

General Relativity and Quantum Cosmology · Physics 2016-10-13 Ernesto F. Eiroa , Emilio Rubin de Celis , Claudio Simeone

Formation of specific static wormhole models is discussed, by assuming an $f(\textit{R}, \textit{T}) = R + 2 \lambda T$ extended theory of gravity, $T =- \rho + P_{r} + 2P_{l}$ being the trace of the energy momentum tensor. In the first…

General Relativity and Quantum Cosmology · Physics 2019-01-09 Emilio Elizalde , Martiros Khurshudyan

We build five-dimensional spherically symmetric wormholes within the DGP theory. We calculate the energy localized on the shell, and we find that the wormholes could be supported by matter not violating the energy conditions. We also show…

General Relativity and Quantum Cosmology · Physics 2010-09-07 Martín G. Richarte
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