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In this paper, we study the spherically symmetric Dirac star model in the presence of a phantom field, obtaining a traversable wormhole solution in non-trivial topological spacetime. This solution exhibits asymmetry in both the field…

General Relativity and Quantum Cosmology · Physics 2023-09-29 Chen-Hao Hao , Shi-Xian Sun , Long-Xing Huang , Rong Zhang , Xin Su , Yong-Qiang Wang

The wormhole solution could be found by solving the Einstein field equations with violating the null energy condition (NEC). We represent wormhole solutions in $\kappa(R,T)$ gravity in two different ways. At first, we find the shape…

General Relativity and Quantum Cosmology · Physics 2022-07-27 Susmita Sarkar , Nayan Sarkar , Farook Rahaman , Y Aditya

Rastall's theory belongs to the class of non-conservative theories of gravity. In vacuum, the only non-trivial static, spherically symmetric solution is the Schwarzschild one, except in a very special case. When a canonical scalar field is…

General Relativity and Quantum Cosmology · Physics 2017-03-03 K. A. Bronnikov , J. C. Fabris , O. F. Piattella , E. C. Santos

It is proved that all thin-shell wormholes built from two identical regions of vacuum static, spherically symmetric space-times have a negative shell surface energy density in any scalar-tensor theory of gravity with a non-ghost massless…

General Relativity and Quantum Cosmology · Physics 2009-07-22 Kirill A. Bronnikov , Alexei A. Starobinsky

We study the stability of static, spherically symmetric, traversable wormholes existing due to conformal continuations in a class of scalar-tensor theories with zero scalar field potential (so that Fisher's well-known scalar-vacuum solution…

General Relativity and Quantum Cosmology · Physics 2016-08-31 K. A. Bronnikov , S. V. Grinyok

We consider static and spherically symmetric wormhole solutions in extended metric-affine theories of gravity supposing that stability and traversability of these objects can be achieved by means of the geometric degrees of freedom. In…

General Relativity and Quantum Cosmology · Physics 2023-11-17 Vittorio De Falco , Salvatore Capozziello

Based on the rigid positive energy theorem we proved the uniqueness of static spherically symmetric traversable wormholes with two asymptotically flat ends, being the higher-dimensional solutions of Einstein scalar phantom field. The proof…

High Energy Physics - Theory · Physics 2018-02-14 Marek Rogatko

We find static spherically symmetric solutions of scale invariant $R^2$ gravity. The latter has been shown to be equivalent to General Relativity with a positive cosmological constant and a scalar mode. Therefore, one expects that solutions…

High Energy Physics - Theory · Physics 2015-02-23 Alex Kehagias , Costas Kounnas , Dieter Lust , Antonio Riotto

In this work, we find novel static and spherically symmetric wormhole geometries using a three-form field. By solving the gravitational field equations, we find a variety of analytical and numerical solutions and show that it is possible…

General Relativity and Quantum Cosmology · Physics 2018-08-10 Bruno J. Barros , Francisco S. N. Lobo

Among the several modified/extended gravity paradigms, the concept of antisymmetric connections leading to space-time torsion can be traced back to Cartan. More recently, developments in string theory have suggested the existence of a…

General Relativity and Quantum Cosmology · Physics 2023-06-01 Parangam Goswami , Anshuman Baruah , Atri Deshamukhya

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 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 consider rotating wormhole solutions supported by a complex phantom scalar field with a quartic self-interaction, where the phantom field induces the rotation of the spacetime. The solutions are regular and asymptotically flat. A subset…

General Relativity and Quantum Cosmology · Physics 2019-08-21 Xiao Yan Chew , Vladimir Dzhunushaliev , Vladimir Folomeev , Burkhard Kleihaus , Jutta Kunz

By choosing an appropriate vielbein basis, we obtain a class of spherically-symmetric solutions in $f(T)$ gravities. The solutions are asymptotic to Minkowski spacetimes with leading falloffs the same as those of the Schwarzschild black…

High Energy Physics - Theory · Physics 2017-06-21 Zhan-Feng Mai , H. Lu

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 study compact configurations with a nontrivial wormholelike spacetime topology supported by a complex ghost scalar field with a quartic self-interaction. For this case, we obtain regular asymptotically flat equilibrium solutions…

General Relativity and Quantum Cosmology · Physics 2018-01-09 Vladimir Dzhunushaliev , Vladimir Folomeev , Burkhard Kleihaus , Jutta Kunz

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

Models of static wormholes are investigated in the framework of $f(\textit{R}, \textit{T})$ gravity ($\textit{R}$ being the curvature scalar, and $\textit{T}$ the trace of the energy momentum tensor). An attempt to link the energy density…

General Relativity and Quantum Cosmology · Physics 2018-12-31 Emilio Elizalde , Martiros Khurshudyan

We discuss several properties of static, spherically symmetric wormholes with particular emphasis on the behavior of causal geodesics and the propagation of linear fields. We show there always exist null geodesics which are trapped in a…

General Relativity and Quantum Cosmology · Physics 2014-06-17 Olivier Sarbach , Thomas Zannias

We present new, asymptotically flat, static, spherically symmetric and traversable wormhole solutions in General Relativity which are supported by a family of ghost scalar fields with quartic potential. This family consists of a particular…

General Relativity and Quantum Cosmology · Physics 2019-10-31 Belen Carvente , Víctor Jaramillo , Juan Carlos Degollado , Darío Núñez , Olivier Sarbach
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