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Related papers: Traversable wormholes: Some simple examples

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The massless conformally coupled scalar field is characterized by the so-called "new improved stress-energy tensor", which is capable of classically violating the null energy condition. When coupled to Einstein gravity we find a…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Carlos Barcelo , Matt Visser

In this paper we analyze the traversability of static and evolving Schwarzschild-Anti-de Sitter wormholes. The wormhole metric under consideration is not asymptotically flat. Hence one can only embed this metric into the Euclidean space for…

General Relativity and Quantum Cosmology · Physics 2024-10-15 Sheng-Fu Zhang , Rui-Hui Lin

It is shown that among the different classes of claimed static wormhole solutions of the vacuum Brans-Dicke theory only Brans Class I solution with coupling constant $\omega$ less than -1.5 (excluding the point $\omega =2$) gives rise to…

General Relativity and Quantum Cosmology · Physics 2011-07-19 Arunava Bhadra , Kabita Sarkar

We present a traversable wormhole solution using the traceless $f(R,T)$ theory of gravity. In the $f(R,T)$ gravity, the Ricci scalar $R$ in the Einstein-Hilbert action is replaced by a function of $R$ and trace of the energy momentum tensor…

General Relativity and Quantum Cosmology · Physics 2021-09-02 Parbati Sahoo , P. H. R. S. Moraes , Marcelo M. Lapola , P. K. Sahoo

The theoretical construction of a traversable wormhole proposed by Morris and Thorne maintains complete control over the geometry by assigning both the shape and redshift functions, thereby leaving open the determination of the…

General Relativity and Quantum Cosmology · Physics 2020-07-27 Peter K. F. Kuhfittig

It is well known that a Morris-Thorne wormhole can only be held open by violating the null energy condition, physically realizable by the use of "exotic matter." Unfortunately, even a small or moderately-sized wormhole would have a radial…

General Relativity and Quantum Cosmology · Physics 2020-06-29 Peter K. F. Kuhfittig

We construct a model of a rotating wormhole made by cutting and pasting two Kerr spacetimes. As a result, we obtain a rotating thin-shell wormhole with exotic matter at the throat. Two candidates for the exotic matter are considered: (i) a…

General Relativity and Quantum Cosmology · Physics 2015-03-18 P. E. Kashargin , S. V. Sushkov

We have proposed a novel shape function on which the metric that models traversable wormholes is dependent. Using this shape function, the energy conditions, equation of state and anisotropy parameter are analyzed in $f(R)$ gravity,…

General Relativity and Quantum Cosmology · Physics 2020-05-19 Gauranga C. Samanta , Nisha Godani , Kazuharu Bamba

Traversable wormholes, studied by Morris and Thorne \cite{Morris1} in general relativity, are investigated in this research paper in $f(R,T)$ gravity by introducing a new form of non-linear $f(R,T)$ function. By using this novel function,…

General Physics · Physics 2020-01-08 Nisha Godani , Gauranga C. Samanta

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

Ghost stars are compact configurations characterized by an arbitrarily small total mass. Such objects require regions of negative energy density -a condition typically regarded as unphysical within the context of conventional stellar…

General Relativity and Quantum Cosmology · Physics 2026-01-01 Alberto Guilabert , Ernesto Fuenmayor , Pedro Bargueño , Ernesto Contreras

In this paper, we introduce higher dimensional thin-shell wormholes in pure Gauss-Bonnet gravity. The focus is on thin-shell wormholes constructed by $N\geq5$-dimensional spherically symmetric vacuum solutions. The results suggest that,…

General Relativity and Quantum Cosmology · Physics 2020-11-25 S. Danial Forghani , S. Habib Mazharimousavi

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

In the paper, we analyze some physical properties of static traversable WH within the framework of $f(R,T)$ modified gravitational theory. Firstly, we explore the validity of the null, weak, dominant and strong energy conditions for…

General Relativity and Quantum Cosmology · Physics 2024-03-21 Jianbo Lu , Mou Xu , Jing Guo , Ruonan Li

In this paper, we evaluate traversable wormhole solutions through Karmarkar condition in $f(R,T)$ theory, where $T$ is the trace of the energy-momentum tensor and $R$ represents the Ricci scalar. We develop a wormhole shape function for the…

General Relativity and Quantum Cosmology · Physics 2023-03-06 M. Sharif , Arooj Fatima

Traversible wormhole space-times are found as static, spherically symmetric solutions to the Einstein equations with ingoing and outgoing pure ghost radiation, i.e. pure radiation with negative energy density. Switching off the radiation…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Sean A. Hayward

It has recently been shown that traversable wormholes may be supported by phantom energy. In this work phantom wormhole geometries are modelled by matching an interior traversable wormhole solution, governed by the equation of state…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Francisco S. N. Lobo

We study traversable wormhole solutions in pure gauged $N\!=\!2$ supergravity with and without electromagnetic fields, which are locally isometric under $\mathrm{SO}(2,1)\!\times\!\mathrm{SO}(1,1)$. The model allows for 1/2-BPS wormhole…

High Energy Physics - Theory · Physics 2020-10-28 Andres Anabalon , Bernard de Wit , Julio Oliva

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

A fundamental property in wormhole physics is the flaring-out condition of the throat, which through the Einstein field equation entails the violation of the null energy condition. In the context of modified theories of gravity, it has also…

General Relativity and Quantum Cosmology · Physics 2012-11-07 Francisco S. N. Lobo