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In recent, Kar.S et.al [ Phys Rev D 67,044005 (2003) ] have obtained static spherically symmetric solutions of the Einstein-Kalb-Ramond field equations. We have shown that their solutions, indeed, represent Wormholes.

General Relativity and Quantum Cosmology · Physics 2010-11-11 F. Rahaman , M. Kalam , A. Ghosh

In this work, we analyse the evolution of time-dependent traversable wormhole geometries in a Friedmann-Lema\^{i}tre-Robertson-Walker background in the context of the scalar-tensor representation of hybrid metric-Palatini gravity. We deduce…

General Relativity and Quantum Cosmology · Physics 2021-04-06 Mahdi Kord Zangeneh , Francisco S. N. Lobo

It is shown that among the different classes of claimed static wormhole solutions of the vacuum Brans-Dicke theory only Brans Class I solution with coupling constant $\omega$ less than -1.5 (excluding the point $\omega =2$) gives rise to…

General Relativity and Quantum Cosmology · Physics 2011-07-19 Arunava Bhadra , Kabita Sarkar

We discuss new exact solutions of a three-parameter nonminimal Einstein-Maxwell model. The solutions describe static spherically symmetric objects with and without center, supported by an electric field nonminimally coupled to gravity. We…

General Relativity and Quantum Cosmology · Physics 2010-04-16 Alexander B. Balakin , José P. S. Lemos , Alexei E. Zayats

We develop a number of novel "black-bounce" spacetimes. These are specific regular black holes where the "area radius" always remains non-zero, thereby leading to a "throat" that is either timelike (corresponding to a traversable wormhole),…

General Relativity and Quantum Cosmology · Physics 2021-05-05 Francisco S. N. Lobo , Manuel E. Rodrigues , Marcos V. de S. Silva , Alex Simpson , Matt Visser

We study the static and spherically symmetric wormhole spacetime configurations at present time in a viscous universe. Considering three classes of viscous models, i.e., bulk viscosity as a function of Hubble constant $H_0$, present cosmic…

General Relativity and Quantum Cosmology · Physics 2022-01-10 Deng Wang

We consider $f(R, T)$ theory of gravity, in which the gravitational Lagrangian is given by an arbitrary function of the Ricci scalar and the trace of the energy-momentum tensor, to study static spherically symmetric wormhole geometries…

General Relativity and Quantum Cosmology · Physics 2021-08-03 Ayan Banerjee , M. K. Jasim , Sushant G. Ghosh

We study spherically symmetric thin-shell wormholes in a string cloud background in (3+1)-dimensional spacetime. The amount of exotic matter required for the construction, the traversability and the stability under radial perturbations, are…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Martin Richarte , Claudio Simeone

In this paper we study classical general relativistic static wormhole configurations with pseudo-spherical symmetry. We show that in addition to the hyperbolic wormhole solutions discussed by Lobo and Mimoso in the Ref. Phys.\ Rev.\ D {\bf…

General Relativity and Quantum Cosmology · Physics 2015-06-26 Mauricio Cataldo , Luis Liempi , Pablo Rodriguez

A static wormhole solution for gravity in vacuum is found for odd dimensions greater than four. In five dimensions the gravitational theory considered is described by the Einstein-Gauss-Bonnet action where the coupling of the quadratic term…

High Energy Physics - Theory · Physics 2008-11-26 Gustavo Dotti , Julio Oliva , Ricardo Troncoso

The present work investigates the general wormhole solution in Einstein gravity with an exponential shape function around an ultrastatic and a finite redshift geometry. The geodesic motion around the wormholes is studied in which the…

General Relativity and Quantum Cosmology · Physics 2024-06-06 Ayanendu Dutta , Dhritimalya Roy , Subenoy Chakraborty

We consider the construction of generic spherically symmetric thin-shell traversable wormhole spacetimes in standard general relativity. By using the cut-and-paste procedure, we comprehensively analyze the stability of arbitrary spherically…

General Relativity and Quantum Cosmology · Physics 2012-08-16 Nadiezhda Montelongo Garcia , Francisco S. N. Lobo , Matt Visser

This paper investigates the massive gauge field within spacetime context from a $\mathbb{Z}_2$ quotient of the constant curvature black hole. We investigate how the matter field's back reaction affects the spacetime geometry, considering…

General Relativity and Quantum Cosmology · Physics 2024-10-22 Ankit Anand , Ruben Campos Delgado , Daris Samart

In this paper, we present the spherically symmetric Proca star in the presence of a phantom field and obtain a traversable wormhole solution for non-trivial topological spacetime. Using numerical methods, symmetric solutions and asymmetric…

General Relativity and Quantum Cosmology · Physics 2023-11-30 Xin Su , Chen-Hao Hao , Ji-Rong Ren , Yong-Qiang Wang

In this letter we point out the existence of solutions to General Relativity with a negative cosmological constant in four dimensions, which contain solitons as well as traversable wormholes. The latter connect two asymptotically locally…

High Energy Physics - Theory · Physics 2019-05-01 Andres Anabalon , Julio Oliva

A wormhole solution in Newtonian gravitation, enhanced through an equation relating the Ricci scalar to the mass density, is presented. The wormhole inhabits a spherically symmetric curved space, with one throat and two asymptotically flat…

General Relativity and Quantum Cosmology · Physics 2016-03-24 José P. S. Lemos , Paulo Luz

The CGHS two-dimensional dilaton gravity model is generalized to include a ghost Klein-Gordon field, i.e. with negative gravitational coupling. This exotic radiation supports the existence of static traversible wormhole solutions, analogous…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Sean A. Hayward , Sung-Won Kim , Hyunjoo Lee

Exact solutions of traversable wormholes are found under the assumption of spherical symmetry and the existence of a {\it non-static} conformal symmetry, which presents a more systematic approach in searching for exact wormhole solutions.…

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

For static, spherically symmetric space-times in general relativity (GR), a no-go theorem is proved: it excludes the existence of wormholes with flat and/or AdS asymptotic regions on both sides of the throat if the source matter is…

General Relativity and Quantum Cosmology · Physics 2018-01-03 K. A. Bronnikov , K. A. Baleevskikh , M. V. Skvortsova