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We argue that a spherically symmetric traversable wormhole solution of the Einstein field equations can be supported by minimally coupled self-interacting scalar field which allows a spontaneous symmetry breaking of the field around the…

General Relativity and Quantum Cosmology · Physics 2025-03-05 Soumya Chakrabarti , Chiranjeeb Singha

There are some gravitational theories in which the ordinary energy-momentum conservation law is not valid in the curved spacetime. Rastall gravity is one of the known theories in this regard which includes a non-minimal coupling between…

General Relativity and Quantum Cosmology · Physics 2018-04-17 H. Moradpour , N. Sadeghnezhad , S. H. Hendi

There are hints that the connectivity of space-time in quantum gravity could emerge from entanglement, and it has further been proposed that any two entangled particles may be connected by a quantum wormhole. One way to test this proposal…

General Relativity and Quantum Cosmology · Physics 2021-08-27 Edward Wilson-Ewing

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

Wormholes are fascinating alternatives to black hole geometries. In this paper, we have studied a special case of wormhole solution in the context of $R=0$ spacetime. Our approximate analytical calculations show that under a strictly static…

General Relativity and Quantum Cosmology · Physics 2026-05-06 Shauvik Biswas

The Kalb-Ramond field is a background tensor field that arises in string theory and violates local Lorentz symmetry of spacetime, upon acquiring the Vacuum Expectation Value. A non-minimal coupling between the Kalb-Ramond VEV and the Ricci…

General Relativity and Quantum Cosmology · Physics 2026-04-28 Arya Dutta , Farook Rahaman

We study the structure and stability of traversable wormholes built as (spherically symmetric) thin shells in the context of Palatini $f(\mathcal{R})$ gravity. Using a suitable junction formalism for these theories we find that the…

General Relativity and Quantum Cosmology · Physics 2020-11-11 Francisco S. N. Lobo , Gonzalo J. Olmo , Emanuele Orazi , Diego Rubiera-Garcia , Azmat Rustam

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

This paper examines the effects of charge on traversable wormhole structure in $f(R,T)$ theory. For this purpose, we use the embedding class-I approach to build a wormhole shape function from the static spherically symmetric spacetime. The…

General Relativity and Quantum Cosmology · Physics 2023-08-21 M. Sharif , Arooj Fatima

The present work deals with a spherically symmetric space-time which is asymptotically (at spatial infinity) FRW space-time and represents wormhole configuration: The matter component is divided into two parts--(a) dissipative but…

General Relativity and Quantum Cosmology · Physics 2015-01-27 Supriya Pan , Subenoy Chakraborty

Properties of $n(\ge 5)$-dimensional static wormhole solutions are investigated in Einstein-Gauss-Bonnet gravity with or without a cosmological constant $\Lambda$. We assume that the spacetime has symmetries corresponding to the isometries…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Hideki Maeda , Masato Nozawa

The present work is an attempt to find possible traversable wormhole solutions in static spherically symmetric space-time supported by anisotropic matter field. Part of the work could be considered as a generalization of the work in Phys.…

General Relativity and Quantum Cosmology · Physics 2019-03-11 Shibaji Halder , Subhra Bhattacharya , Subenoy Chakraborty

We study the problem of existence of static spherically symmetric wormholes supported by the kink-like configuration of a scalar field. With this aim we consider a self-consistent, real, nonlinear, nonminimally coupled scalar field $\phi$…

General Relativity and Quantum Cosmology · Physics 2009-11-07 S. V. Sushkov , S. -W. Kim

We present a systematic study of exact solutions for traversable wormhole geometries in a static and hyperbolic symmetric spacetime. In the conventional form of studying wormhole geometry, traversability requires the presence of exotic…

General Relativity and Quantum Cosmology · Physics 2025-07-25 Roberto Avalos , Ernesto Contreras , Daniel Brito , Ernesto Fuenmayor

Although wormholes can be treated as topological objects in spacetime and from a global point-of-view, a precise definition of what a wormhole throat is and where it can be located can be developed and treated entirely in terms of local…

General Relativity and Quantum Cosmology · Physics 2007-05-23 David Hochberg , Matt Visser

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 numerically the stability of Morris & Thorne's first traversible wormhole, shown previously by Ellis to be a solution for a massless ghost Klein-Gordon field. Our code uses a dual-null formulation for spherically symmetric…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Hisa-aki Shinkai , Sean A. Hayward

Wormholes are exotic compact objects characterized by the absence of essential singularities and horizons, acting as slender bridges linking two distinct regions of spacetime. Despite their theoretical significance, they remain however…

General Relativity and Quantum Cosmology · Physics 2025-02-25 Ciro De Simone , Vittorio De Falco , Salvatore Capozziello

We clarify the relationship between rotation and the energy condition for stationary rotating wormhole solutions of the Einstein equations coupled to a phantom field in five-dimensional spacetime with equal angular momenta, particularly…

General Relativity and Quantum Cosmology · Physics 2026-03-16 Keiya Uemichi , Yasutaka Koga , Daiki Saito , Chul-Moon Yoo , Daisuke Yoshida

We study geodesic motion near the throats of asymptotically flat, static, spherically~symmetric traversable wormholes supported by a self-gravitating minimally coupled phantom scalar field with an arbitrary self-interaction potential. We…

General Relativity and Quantum Cosmology · Physics 2020-10-20 Ivan Potashov , Julia Tchemarina , Alexander Tsirulev