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Related papers: Vacuum static Brans-Dicke wormhole

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Gauss-Bonnet formula is used to derive a new and simple theorem of nonexistence of vacuum static nonsingular lorentzian wormholes. We also derive simple proofs for the nonexistence of lorentzian wormhole solutions for some classes of static…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Alberto Saa

A traversable wormhole solution of general scalar-tensor field equations is presented. We have shown, after a numerical analysis for the behavior of the scalar field of Brans-Dicke theory, that the solution is completely singularity--free.…

General Relativity and Quantum Cosmology · Physics 2009-10-31 L. A. Anchordoqui , M. L. Trobo , H. Vucetich , F. Zyserman

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

Recently, a class of spherically symmetric thin-shell wormholes in Brans-Dicke gravity have been introduced. Such wormholes can be supported by matter satisfying the weak energy condition (WEC). In this paper, we first obtain all the exact…

General Relativity and Quantum Cosmology · Physics 2015-05-28 Xiaojun Yue , Sijie Gao

In this paper new exact solutions in eight dimensional Lovelock theory will be presented. These solutions are vacuum static wormhole, black hole and generalized Bertotti-Robinson space-times with nontrivial torsion. All the solutions have a…

High Energy Physics - Theory · Physics 2008-11-26 Fabrizio Canfora , Alex Giacomini

The static, cylindrically symmetric vacuum solutions with a cosmological constant in the framework of the Brans-Dicke theory are investigated. Some of these solutions admitting Lorentz boost invariance along the symmetry axis correspond to…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Ozgur Delice

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

It is known that the formation of a wormhole typically involves a violation of the Weak Energy Condition (WEC), but the reverse is not necessarily true. In the context of Brans-Dicke gravity, the $\textit{generalized}$ Campanelli-Lousto…

General Relativity and Quantum Cosmology · Physics 2024-10-08 Hoang Ky Nguyen , Mustapha Azreg-Aïnou

In the present study we search for a new class of wormhole solutions in the framework of Brans-Dicke (BD) theory in the presence of anisotropic matter distribution. Considering a linear equation of state (EoS) between radial pressure and…

General Relativity and Quantum Cosmology · Physics 2025-09-16 Amir Hadi Ziaie , Naser Sadeghnezhad , Akbar Jahan

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 propose a unimodular version of the Brans-Dicke theory designed with a constrained Lagrangian formulation. The resulting field equations are traceless. The vacuum solutions in the cosmological background reproduce the corresponding…

General Relativity and Quantum Cosmology · Physics 2022-07-28 Alexandre M. R. Almeida , Júlio C. Fabris , Mahamadou Hamani Daouda , Richard Kerner , Hermano Velten , Wiliam S. Hipólito-Ricaldi

Noether symmetry has been invoked to explore the forms of a couple of coupling parameters and the potential appearing in a general scalar-tensor theory of gravity in the background of Robertson-Walker space-time. Exact solutions of…

Cosmology and Nongalactic Astrophysics · Physics 2018-12-10 Abhik Kumar Sanyal , Ranajit Mandal

In this paper, we provide a vacuum solution with torsion in quadratic Riemann-curvature gravity. Physically, the solution means that vacuum can have a nonzero vacuum field with large torsion. We show that the Einstein-Hilbert action can be…

High Energy Physics - Theory · Physics 2012-09-04 Kouzou Nishida

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

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 study the Brans-Dicke theory of gravity in Riemann-Cartan space-times, and obtain general torsion solutions, which are completely determined by Brans-Dicke scalar field $\Phi$, in the false vacuum energy dominated epoch. The substitution…

General Relativity and Quantum Cosmology · Physics 2012-12-27 Yu-Huei Wu , Chih-Hung Wang

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 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

In this paper, we explore the nucleation of vacuum bubbles in the Brans-Dicke type theory of gravity. In the Euclidean signature, we evaluate the fields at the vacuum bubbles as solutions of the Euler-Lagrange equations of motion as well as…

High Energy Physics - Theory · Physics 2011-08-08 Hongsu Kim , Bum-Hoon Lee , Wonwoo Lee , Young Jae Lee , Dong-han Yeom

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