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Related papers: Ring wormholes and time machines

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We construct a static axisymmetric wormhole from the gravitational field of two Schwarzschild particles which are kept in equilibrium by strings (ropes) extending to infinity. The wormhole is obtained by matching two three-dimensional…

General Relativity and Quantum Cosmology · Physics 2014-11-17 F. Schein , P. C. Aichelburg , W. Israel

We construct traversable wormholes by starting with simple four-dimensional classical solutions respecting the null energy condition and containing a pair of oppositely charged black holes connected by a non-traversable wormhole. We then…

High Energy Physics - Theory · Physics 2020-01-03 Zicao Fu , Brianna Grado-White , Donald Marolf

We apply duality rotations and complex transformations to the Schwarzschild metric to obtain wormhole geometries with two asymptotically flat regions connected by a throat. In the simplest case these are the well-known wormholes supported…

High Energy Physics - Theory · Physics 2016-08-03 Gary W. Gibbons , Mikhail S. Volkov

A wormhole is constructed by cutting and joining two spacetimes satisfying the low energy string equations with a dilaton field. In spacetimes described by the "string metric" the dilaton energy-momentum tensor need not satisfy the weak or…

General Relativity and Quantum Cosmology · Physics 2010-11-19 Dan N. Vollick

We consider rotating wormhole solutions in general relativity supported by a complex non-phantom spinor field (which provides a nontrivial spacetime topology) and electromagnetic fields. The solutions are asymmetric, regular, asymptotically…

General Relativity and Quantum Cosmology · Physics 2026-04-21 Vladimir Dzhunushaliev , Vladimir Folomeev

Wormholes are non-trivial topological structures that arise as exact solutions to Einstein's field equations, theoretically connecting distinct regions of spacetime via a throat-like geometry. While static traversable wormholes necessarily…

General Relativity and Quantum Cosmology · Physics 2025-07-22 Mahdi Kord Zangeneh , Francisco S. N. Lobo

We construct regular multi-wormhole solutions to a gravitating $\sigma$ model in three space-time dimensions, and extend these solutions to cylindrical traversable wormholes in four and five dimensions. We then discuss the possibility of…

General Relativity and Quantum Cosmology · Physics 2016-08-31 Gérard Clément

In this work we show the existence of traversable wormhole and time-machine solutions in a modified theory of gravity where matter and curvature are nonminimally coupled. Those solutions present a nontrivial redshift function and exist even…

High Energy Physics - Theory · Physics 2013-10-24 Orfeu Bertolami , Ricardo Zambujal Ferreira

Beginning with a brief review of the regular space-time with asymptotically Minkowski core, we can consider two copies of the space-time connected through a short-throat wormhole whose radius of mouth is equal to or larger than an extremal…

General Relativity and Quantum Cosmology · Physics 2022-01-14 Wei Hong , Jun Tao , Tong-Jie Zhang

In this talk I discuss pertinence of the wormholes to the problem of circumventing the light speed barrier and present a specific class of wormholes. The wormholes of this class are static and have arbitrarily wide throats, which makes them…

General Relativity and Quantum Cosmology · Physics 2007-05-23 S. V. Krasnikov

We investigate the response of the traversable wormholes to the external perturbations through finding their characteristic frequencies and time-domain profiles. The considered solution describes traversable wormholes between the branes in…

General Relativity and Quantum Cosmology · Physics 2011-07-19 R. A. Konoplya , C. Molina

This paper generalizes the static and spherically symmetric traversable wormhole geometry to a rotating axially symmetric one with a time-dependent angular velocity by means of an exact solution. It was found that the violation of the weak…

General Relativity and Quantum Cosmology · Physics 2010-11-19 Peter K. F. Kuhfittig

We obtain traversable wormhole and time machine solutions of the field equations of an alternative of gravity with non-minimally curvature-matter coupling. Our solutions exhibit a non-trivial redshift function and allow for matter that…

General Relativity and Quantum Cosmology · Physics 2013-05-30 Orfeu Bertolami , Ricardo Zambujal Ferreira

A dynamical theory of traversable wormholes is detailed in spherical symmetry. Generically a wormhole consists of a tunnel of trapped surfaces between two mouths, defined as temporal outer trapping horizons with opposite senses, in mutual…

General Relativity and Quantum Cosmology · Physics 2009-06-30 Sean A. Hayward

This Letter aims to advance unexplored properties of a new class of Closed Timelike Curves recently discovered in scalar-tensor gravity, reported in Universe 9, 467 (2023) and Eur.$\,$Phys.$\,$J.$\,$C 83, 626 (2023). Therein, it was shown…

General Relativity and Quantum Cosmology · Physics 2024-07-26 Hoang Ky Nguyen , Francisco S. N. Lobo

We seek wormholes among rotating cylindrically symmetric configurations in general relativity. Exact wormhole solutions are presented with such sources of gravity as a massless scalar field, a cosmological constant, and a scalar field with…

General Relativity and Quantum Cosmology · Physics 2016-03-30 K. A. Bronnikov , V. G. Krechet

We consider novel wormhole solutions supported by a matter content that minimally violates the null energy condition. More specifically, we consider an equation of state in which the sum of the energy density and radial pressure is…

General Relativity and Quantum Cosmology · Physics 2014-11-10 Mariam Bouhmadi-Lopez , Francisco S. N. Lobo , Prado Martin-Moruno

In 6D general relativity with a scalar field as a source of gravity, a new type of static wormhole solutions is presented: such wormholes connect our universe with a small 2D extra subspace with a universe where this extra subspace is…

General Relativity and Quantum Cosmology · Physics 2016-12-07 K. A. Bronnikov , M. V. Skvortsova

We review recent work on wormhole geometries in the context of modified theories of gravity, in particular, in f(R) gravity and with a nonminimal curvature-matter coupling, and in the recently proposed hybrid metric-Palatini theory. In…

General Relativity and Quantum Cosmology · Physics 2013-10-18 Francisco S. N. Lobo

We review a new traversable-wormhole solution of the gravitational field equation of general relativity without exotic matter. Instead of having exotic matter to keep the wormhole throat open, the solution relies on a 3-dimensional…

General Relativity and Quantum Cosmology · Physics 2023-07-25 Frans R. Klinkhamer
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