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We have obtained two classes of $(n+1)$-dimensional wormhole solutions using a traceless energy-momentum tensor in Brans-Dicke theory of gravity. The first class contains wormhole solutions in an open geometry while the second contains…

High Energy Physics - Theory · Physics 2010-04-06 E. Ebrahimi , N. Riazi

Recently, traversable wormhole geometries were constructed in the context of f(R) gravity. The latter is equivalent to a Brans-Dicke theory with a coupling parameter w=0, which is apparently excluded from the narrow interval, -3/2<w<-4/3,…

General Relativity and Quantum Cosmology · Physics 2010-05-12 Francisco S. N. Lobo , Miguel A. Oliveira

Following the recent theory of Lovelock-Brans-Dicke gravity, we continue to investigate the conditions to support traversable wormholes by the gravitational effects of spacetime parity and topology, which arise from the nonminimal couplings…

General Relativity and Quantum Cosmology · Physics 2016-01-08 David Wenjie Tian

Wormhole configurations in Einstein's general theory of relativity (GR) require exotic matter sources violating the weak energy condition (WEC). Rastall's theory is a generalization of GR in its matter source considering a nonconserved…

General Relativity and Quantum Cosmology · Physics 2024-01-19 Yaghoub Heydarzade , Maryam Ranjbar

A fundamental ingredient in wormhole physics is the presence of exotic matter, which involves the violation of the null energy condition. Although a plethora of wormhole solutions have been explored in the literature, it is useful to find…

General Relativity and Quantum Cosmology · Physics 2015-05-28 Nadiezhda Montelongo Garcia , Francisco S. N. Lobo

We obtain a large class of Lorentzian wormhole spacetimes in scalar-tensor gravity, for which the matter stress energy does satisfy the weak energy condition. Our constructions have zero Ricci scalar and an everywhere finite, non-zero…

General Relativity and Quantum Cosmology · Physics 2016-07-12 Rajibul Shaikh , Sayan Kar

A basic constraint to be satisfied by Brans class I solution for being a traversible wormhole is derived. It is argued that the solution could be a wormhole analogue of the Horowitz-Ross naked black hole. It is further demonstrated that the…

General Relativity and Quantum Cosmology · Physics 2010-03-25 Amrita Bhattacharya , Ilnur Nigmatzyanov , Ramil Izmailov , Kamal K. Nandi

It is shown that three of the four Brans solutions of classes I--IV admit wormhole geometry. Two-way traversable wormholes in the Brans-Dicke theory are allowed not only for the negative values of the coupling parameter w (w<-2), as…

General Relativity and Quantum Cosmology · Physics 2009-06-30 Kamal K. Nandi , Anwarul Islam

In this work wormholes in viable $f(R)$ gravity models are analysed. We are interested in exact solutions for stress-energy tensor components depending on different shape and redshift functions. Several solutions of gravitational equations…

General Relativity and Quantum Cosmology · Physics 2015-03-24 Petar Pavlović , Marko Sossich

We construct a new static spherically symmetric configuration composed of interior and exterior Brans-Dicke vacua matched at a thin matter shell. Both vacua correspond to the same Brans-Dicke coupling parameter $\omega$, however they are…

General Relativity and Quantum Cosmology · Physics 2013-05-29 Sergey V. Sushkov , Sergey M. Kozyrev

Wormhole solutions, bridges that connect different parts of spacetime, were proposed early in the history of General Relativity. Soon after, it was shown that all wormholes violate classical energy conditions, which are non-negativity…

General Relativity and Quantum Cosmology · Physics 2024-07-09 Eleni-Alexandra Kontou

Static axisymmetric thin-shell wormholes are constructed within the framework of the Brans-Dicke scalar-tensor theory of gravity. Examples of wormholes associated with vacuum and electromagnetic fields are studied. All constructions must be…

General Relativity and Quantum Cosmology · Physics 2016-02-12 Ernesto F. Eiroa , Claudio Simeone

The brane cosmology scenario is based on the idea that our Universe is a 3-brane embedded in a five-dimensional bulk. In this work, a general class of braneworld wormholes is explored with $R\neq 0$, where $R$ is the four dimensional Ricci…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Francisco S. N. Lobo

In this paper, we explore higher-dimensional asymptotically flat wormhole geometries in the framework of Gauss-Bonnet (GB) gravity and investigate the effects of the GB term, by considering a specific radial-dependent redshift function and…

General Relativity and Quantum Cosmology · Physics 2015-04-06 Mohammad Reza Mehdizadeh , Mahdi Kord Zangeneh , Francisco S. N. Lobo

A simple Lorentzian vacuum wormhole solution of Brans-Dicke gravitation is presented and analysed. It is shown that such solution holds for both, the Brans-Dicke theory endowed with torsion (for a value of the coupling parameter $\omega >…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Luis A. Anchordoqui , A. G. Grunfeld , Diego F. Torres

Wormholes are hypothetical shortcuts in spacetime that in General Relativity unavoidably violate all of the pointwise energy conditions. In this paper, we consider several wormhole spacetimes that, as opposed to the standard \emph{designer}…

General Relativity and Quantum Cosmology · Physics 2017-12-19 Cecilia Bejarano , Francisco S. N. Lobo , Gonzalo J. Olmo , Diego Rubiera-Garcia

Spherically symmetric thin-shell wormholes are constructed within the framework of Brans-Dicke gravity. It is shown that, for appropriate values of the Brans-Dicke constant, these wormholes can be supported by matter satisfying the energy…

General Relativity and Quantum Cosmology · Physics 2009-06-26 Ernesto F. Eiroa , Martin G. Richarte , Claudio Simeone

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

Wormholes that meet the flare-out condition violate the weak energy condition in classical general relativity. The purpose of this note is to show that even a slight modification of the gravitational theory could, under certain conditions,…

General Relativity and Quantum Cosmology · Physics 2017-02-03 Peter K. F. Kuhfittig

We examine the possibility of static wormhole solutions in the vacuum Brans-Dicke theory both in the original (Jordan) frame and in the conformally rescaled (Einstein) frame. It turns out that, in the former frame, wormholes exist only in a…

General Relativity and Quantum Cosmology · Physics 2009-06-30 K. K. Nandi , B. Bhattacharjee , S. M. K. Alam , J. Evans
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