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Related papers: Some new class of Chaplygin Wormholes

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We construct wormholes in Einstein-vector-Gauss-Bonnet theory where a real massless vector field is coupled to the higher curvature Gauss-Bonnet invariant. We consider three coupling functions which depend on the square of the vector field.…

General Relativity and Quantum Cosmology · Physics 2022-09-28 Simon Barton , Claus Kiefer , Burkhard Kleihaus , Jutta Kunz

A simple model of spacetime foam, made by two different types of wormholes in a semiclassical approximation, is taken under examination: one type is a collection of $N_{w}$ Schwarzschild wormholes, while the other one is made by…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Remo Garattini

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

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

In this paper, we construct an intra-galactic thin shell wormhole joining two copies of identical galactic space times described by the Mannheim-Kazanas de Sitter solution in conformal gravity and study its stability under spherical…

General Relativity and Quantum Cosmology · Physics 2015-06-12 Ivana Bochicchio , Ettore Laserra

We construct static, spherically symmetric, charged traversable wormhole solutions to the Einstein--Maxwell equations, supported by bidirectional (ingoing and outgoing) null dust with negative energy, and discuss a scenario for their…

General Relativity and Quantum Cosmology · Physics 2026-02-16 Yasutaka Koga , Ryota Maeda , Daiki Saito , Keiya Uemichi , Daisuke Yoshida

The theoretical construction of a traversable wormhole proposed by Morris and Thorne maintains complete control over the geometry by assigning both the shape and redshift functions, thereby leaving open the determination of the…

General Relativity and Quantum Cosmology · Physics 2020-07-27 Peter K. F. Kuhfittig

In the present work, we develop and examine a series of exact solutions to Einstein's 5-dimensional field equations in the vacuum, which depend on two constant parameters, $p$ and $q$, which generalize the solutions of L\"u and Mei [8]…

General Relativity and Quantum Cosmology · Physics 2025-11-18 I. A. Sarmiento-Alvarado , Leonel Bixano , Tonatiuh Matos

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

In the context of a model of space-time foam, made by $N$ wormholes we discuss the possibility of having a foam formed by different configurations. An equivalence between Schwarzschild and Schwarzschild-Anti-de Sitter wormholes in terms of…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Remo Garattini

Recently, a modified theory of gravity was presented, which consists of the superposition of the metric Einstein-Hilbert Lagrangian with an $f(\cal R)$ term constructed \`{a} la Palatini. The theory possesses extremely interesting features…

General Relativity and Quantum Cosmology · Physics 2012-12-20 Salvatore Capozziello , Tiberiu Harko , Tomi S. Koivisto , Francisco S. N. Lobo , Gonzalo J. Olmo

In this note two cosmological models representing the flat Friedmann Universe filled with a Chaplygin fluid, with or without dust, are analyzed in terms of the recently proposed "statefinder" parameters. Trajectories of both models in the…

Astrophysics · Physics 2009-11-07 Vittorio Gorini , Alexander Kamenshchik , Ugo Moschella

While wormholes may be just as good a prediction of Einstein's theory as black holes, they are subject to severe restrictions from quantum field theory. In particular, a wormhole can only be held open by violating the null energy condition,…

General Relativity and Quantum Cosmology · Physics 2025-03-31 Peter K. F. Kuhfittig

A multidimensional cosmological model with space-time consisting of $n (n \ge 2)$ Einstein spaces $M_{i}$ is investigated in the presence of a cosmological constant $\Lambda$ and a homogeneous minimally coupled scalar field $\varphi(t)$ as…

General Relativity and Quantum Cosmology · Physics 2009-10-22 U. Bleyer , V. D. Ivashchuk , V. N. Melnikov , A. Zhuk

Considering a energy density of the form $\rho=q\left({\frac{r}{r_0}}\right)^{-n}$( where $q$ is an arbitrary positive constant with dimension of energy density and $n>0$), a shape function is obtained by using field equations of braneworld…

General Relativity and Quantum Cosmology · Physics 2021-09-10 Bikram Ghosh , Saugata Mitra

This study explores asymptotically flat wormhole solutions in $f(Q,T)=\alpha Q+ \beta T$ gravity, expanding upon our prior work (arXiv:2602.00527v1) with matter Lagrangian density, $L_m=-P$ . Here, we examine the implications of employing…

General Relativity and Quantum Cosmology · Physics 2026-05-21 Sodabe Nasirimoghadam , Foad Parsaei , Sara Rastgoo

In this work, we introduce a novel set of asymptotically flat wormhole solutions within the framework of $f(R,T)$ theory of gravity. Considering a linear $f(R,T)=R+ 2\lambda T$ form, we show that a wide variety of wormhole solutions with…

General Relativity and Quantum Cosmology · Physics 2024-08-09 Sara Rastgoo , Foad Parsaei

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

The class of Chaplygin gas models regarded as a candidate of dark energy can be realized by a scalar field, which could drive the variation of the fine structure constant $\alpha$ during the cosmic time. This phenomenon has been observed…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-12 Chao-Jun Feng , Xin-Zhou Li

Traversable wormholes have traditionally been viewed as intrinsically topological entities in some multiply connected spacetime. Here, we show that topology is too limited a tool to accurately characterize a generic traversable wormhole: in…

General Relativity and Quantum Cosmology · Physics 2011-09-30 David Hochberg , Matt Visser
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