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We discuss the structure of a gravitational euclidean instanton obtained through coupling of gravity to electromagnetism. Its topology at fixed $t$ is $S^1\times S^2$. This euclidean solution can be interpreted as a tunnelling to a…

General Relativity and Quantum Cosmology · Physics 2009-10-22 M. Cavaglia' V. de Alfaro , F. de Felice

In this paper, we use the embedding class-I technique to examine the effect of charge on traversable wormhole geometry in the context of $f(\mathcal{G})$ theory, where $\mathcal{G}$ is the Gauss-Bonnet term. For this purpose, we consider…

General Relativity and Quantum Cosmology · Physics 2024-03-04 M. Zeeshan Gul , M. Sharif

We consider a non-static evolving version of the regular "black-bounce"/traversable wormhole geometry recently introduced in JCAP02(2019)042 [arXiv:1812.07114 [gr-qc]]. We first re-write the static metric using Eddington-Finkelstein…

General Relativity and Quantum Cosmology · Physics 2019-06-27 Alex Simpson , Prado Martin-Moruno , Matt Visser

Space-time wormholes were introduced in Wheeler's idea of space-time foam. Traversible wormholes as defined by Morris & Thorne became popular as potential short cuts across the universe and even time machines. More recently, the author…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Sean A. Hayward

In the letter titled ''Traversable Wormholes in General Relativity'' [Phys. Rev. Lett. 128, 091104 (2022)], R. A. Konoplya and A. Zhidenko have constructed an asymmetric wormhole solution, which is not symmetric about the throat and is…

General Relativity and Quantum Cosmology · Physics 2022-06-27 Yong-Qiang Wang , Shao-Wen Wei , Yu-Xiao Liu

We construct stationary Ricci-flat inter-universe Lorentzian wormhole solutions in all D\ge 5 dimensions that connect two flat asymptotic spacetimes. Such a solution can be viewed as the gravity dual of a string tachyon state whose linear…

High Energy Physics - Theory · Physics 2008-11-26 H. Lu , Jianwei Mei

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

We obtain the self-interaction for a point charge in the space-time of a cylindrical thin-shell wormhole connecting two identical locally flat geometries with a constant deficit angle. Although this wormhole geometry is locally…

General Relativity and Quantum Cosmology · Physics 2015-06-11 E. Rubín de Celis , O. P. Santillán , C. Simeone

A general formalism for the dynamics of non rotating cylindrical thin-shell wormholes is developed. The time evolution of the throat is explicitly obtained for thin-shell wormholes whose metric has the form associated to local cosmic…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Ernesto F. Eiroa , Claudio Simeone

A spherically symmetric wormhole in Newtonian gravitation in curved space, enhanced with a connection between the mass density and the Ricci scalar, is presented. The wormhole, consisting of two connected asymptotically flat regions,…

General Relativity and Quantum Cosmology · Physics 2016-03-23 Paulo Luz , José P. S. Lemos

We extend previous proofs that violations of the null energy condition (NEC) are a generic and universal feature of traversable wormholes to completely non-symmetric time-dependent wormholes. We show that the analysis can be phrased purely…

General Relativity and Quantum Cosmology · Physics 2009-10-31 David Hochberg , Matt Visser

Exact solutions of traversable wormholes were recently found under the assumption of spherical symmetry and the existence of a non-static conformal symmetry. In this paper, we verify that in the case of the conformally symmetric spacetimes…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Christian G. Boehmer , Tiberiu Harko , Francisco S. N. Lobo

Wormhole solutions to the equations of general relativity have some spectacular local and global properties. As these unusual features are not explicitly forbidden by known physics, wormholes are considered in various astrophysical and…

General Relativity and Quantum Cosmology · Physics 2022-08-31 Daniel R. Terno

In this article, using gravitational decoupling by means of minimal geometric deformation approach, we obtain a new spherically symmetric and static black hole solution. To progress, we close the system by assuming that the average pressure…

General Relativity and Quantum Cosmology · Physics 2023-08-25 Francisco Tello-Ortiz , Ángel Rincón , A. Alvarez , Saibal Ray

We perform a study to describe motion of charged particles under the influence of electromagnetic and gravitational fields of a slowly rotating wormhole with nonvanishing magnetic moment. We present analytic expression for potentials of…

General Relativity and Quantum Cosmology · Physics 2009-05-27 A. A. Abdujabbarov , B. J. Ahmedov

Wormholes are hypothetical shortcuts in spacetime that in General Relativity unavoidably violate all of the pointwise energy conditions. In this paper, we consider several wormhole spacetimes that, as opposed to the standard \emph{designer}…

General Relativity and Quantum Cosmology · Physics 2017-12-19 Cecilia Bejarano , Francisco S. N. Lobo , Gonzalo J. Olmo , Diego Rubiera-Garcia

We present the first dynamical model of plasma accretion onto traversable wormholes by performing General Relativistic magneto-hydrodynamical (GRMHD) simulations of the flow on both sides of the wormhole. We evolve the ideal MHD equations…

High Energy Astrophysical Phenomena · Physics 2024-05-14 Luciano Combi , Huan Yang , Eduardo Gutierrez , Scott C. Noble , Gustavo E. Romero , Manuela Campanelli

In this article, new wormhole solutions in the framework of General Relativity are presented. Taking advantage of gravitational decoupling by means of minimal geometric deformation approach and, the so-called noncommutative geometry…

General Relativity and Quantum Cosmology · Physics 2023-06-02 Francisco Tello-Ortiz , B. Mishra , A. Alvarez , Ksh. Newton Singh

In this paper we derive new static phantom traversable wormholes by assuming a shape function with a quadratic dependence on the radial coordinate r. We mainly focus our study on wormholes sustained by exotic matter with positive energy…

General Relativity and Quantum Cosmology · Physics 2017-10-11 Mauricio Cataldo , Fabian Orellana

We reconsider the problem of $f(R)$ theories of gravity coupled to Born-Infeld theory of electrodynamics formulated in a Palatini approach, where metric and connection are independent fields. By studying electrovacuum configurations in a…

General Relativity and Quantum Cosmology · Physics 2016-07-25 Cosimo Bambi , Alejandro Cardenas-Avendano , Gonzalo J. Olmo , D. Rubiera-Garcia
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