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Related papers: Brans-Dicke Wormhole Revisited -- II

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In a recent paper, we showed the Jordan frame vacuum Brans Class I solution provided a wormhole analogue to Horowitz-Ross naked black hole in the wormhole range -3/2<{\omega}<-4/3. Thereafter, the solution has been criticized by some…

General Relativity and Quantum Cosmology · Physics 2011-09-16 Amrita Bhattacharya , Ramil Izmailov , Ettore Laserra , Kamal K. Nandi

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

We report the explicit form of the general static, spherically symmetric, and asymptotically flat solution of vacuum Brans-Dicke gravity in the Jordan frame, assuming that the Brans-Dicke scalar field has no singularities or zeros (except…

General Relativity and Quantum Cosmology · Physics 2018-04-25 Valerio Faraoni , Faycal Hammad , Adriana M. Cardini , Thomas Gobeil

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

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

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

We perform analytical and numerical study of static spherically symmetric solutions in the context of Brans-Dicke-like cosmological model by Elizalde et al. with an exponential potential. In this model the phantom regime arises without the…

General Relativity and Quantum Cosmology · Physics 2016-07-05 D. A. Tretyakova , B. N. Latosh , S. O. Alexeyev

Some recent papers have claimed the existence of static, spherically symmetric wormhole solutions to gravitational field equations in the absence of ghost (or phantom) degrees of freedom. We show that in some such cases the solutions in…

General Relativity and Quantum Cosmology · Physics 2014-11-21 K. A. Bronnikov , M. V. Skvortsova , A. A. Starobinsky

In our previous papers we have analyzed the stability of vacuum and electrovacuum static, spherically symmetric space-times in the framework of the Bergmann-Wagoner-Nordtvedt class of scalar-tensor theories (STT) of gravity. In the present…

General Relativity and Quantum Cosmology · Physics 2025-07-24 Kirill A. Bronnikov , Sergei V. Bolokhov , Milena V. Skvortsova , Rustam Ibadov , Feruza Y. Shaymanova

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

Three new classes (II-IV) of solutions of the vacuum low energy effective string theory in four dimensions are derived. Wormhole solutions are investigated in those solutions including the class I case both in the Einstein and in the Jordan…

General Relativity and Quantum Cosmology · Physics 2009-11-10 K. K. Nandi , Yuan-Zhong Zhang

New classes composite vacuum wormhole solutions of Jordan-Brans-Dicke gravitation is presented and analysed. It is shown that such solution holds for both, a bridge between separated Schwarzschild and Brans Universes and for a bridge…

General Relativity and Quantum Cosmology · Physics 2008-12-31 S. M. Kozyrev , S. V. Sushkov

Motivated by statements in the literature which contradict two general theorems, the static and spherically symmetric Brans solutions of scalar-tensor gravity are analyzed explicitly in both the Jordan and the Einstein conformal frames.…

General Relativity and Quantum Cosmology · Physics 2016-11-15 V. Faraoni , F. Hammad , S. D. Belknap-Keet

Using the ansatz of Matos and N\'{u}\~{n}ez, the present article proposes an algorithm for generating several classes, not all independent, of asymptotically flat rotating wormhole solutions in the Brans-Dicke Theory. The algorithm allows…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Kamal K. Nandi , Yuan-Zhong Zhang

Static, spherically symmetric configurations of gravity with nonminimally coupled scalar fields are considered in D-dimensional space-times in the framework of generalized scalar-tensor theories. We seek special cases when the system has no…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Kirill A. Bronnikov

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

A simple Heckmann's vacuum wormhole solution of Jordan-Brans-Dicke gravitation is presented and analysed. It is shown that in contrast with class I Brans solution where the throat radius becomes real when $\omega < -4/3$ here it becomes…

General Relativity and Quantum Cosmology · Physics 2015-03-17 S. M. Kozyrev

It is shown that among the four classes of the static spherically symmetric solution of the vacuum Brans-Dicke theory of gravity only two are really independent. Further by matching exterior and interior (due to physically reasonable…

General Relativity and Quantum Cosmology · Physics 2010-11-19 Arunava Bhadra , Kabita Sarkar

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

We consider a modified Brans-Dicke theory in which except the usual Brans-Dicke parameter a new dimensionful parameter appears which modifies the kinetic term of the scalar field coupled to gravity. Solving the coupled Einstein-Klein-Gordon…

General Relativity and Quantum Cosmology · Physics 2020-03-18 Eleftherios Papantonopoulos , Christoforos Vlachos
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