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Related papers: Cylindrical wormholes in DGP gravity

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This paper introduces a new type of thin-shell wormhole constructed from a special class of compact stellar objects rather than black holes. The construction and concomitant investigation of the stability to linearized radial perturbations…

General Relativity and Quantum Cosmology · Physics 2018-02-15 Peter K. F. Kuhfittig

In this work, we explore asymptotically flat charged thin-shell wormholes of third order Lovelock gravity in higher dimensions, taking into account the cut-and-paste technique. Using the generalized junction conditions, we determine the…

General Relativity and Quantum Cosmology · Physics 2015-08-19 Mohammad Reza Mehdizadeh , Mahdi Kord Zangeneh , Francisco S. N. Lobo

Wormhole solutions in a generalized hybrid metric-Palatini matter theory, given by a gravitational Lagrangian $f\left(R,\cal{R}\right)$, where $R$ is the metric Ricci scalar, and $\mathcal{R}$ is a Palatini scalar curvature defined in terms…

General Relativity and Quantum Cosmology · Physics 2018-10-03 João Luís Rosa , José P. S. Lemos , Francisco S. N. Lobo

We present a four-dimensional Planck-scale corrected quadratic extension of General Relativity (GR) where no a priori relation between metric and connection is imposed (Palatini formalism). Static spherically symmetric electrovacuum…

High Energy Physics - Theory · Physics 2015-12-09 Francisco S. N. Lobo , Gonzalo J. Olmo , D. Rubiera-Garcia

It is generally agreed that the acceleration of the Universe can best be explained by the presence of dark or phantom energy. The equation of state of the latter shows that the null energy condition is violated. Such a violation is the…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Mubasher Jamil , Peter K. F. Kuhfittig , Farook Rahaman , Sk. A Rakib

Wormholes and black holes have traditionally been treated a quite separate objects with relatively little overlap. The possibility of a connection arises in that wormholes, if they exist, might have profound influence on black holes, their…

General Relativity and Quantum Cosmology · Physics 2013-08-27 Matt Visser , David Hochberg

We consider D-particles coupled to the CGHS dilaton gravity and obtain the exact wormhole geometry and trajectories of D-particles by introducing the exotic matter. The initial static wormhole background is not stable after infalling…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Won Tae Kim , Edwin J. Son

In the conventional method of studying wormhole (WH) geometry, traversability requires the presence of exotic matter, which also provides negative gravity effects to keep the wormhole throat open. In dRGT massive gravity theory, we produce…

General Relativity and Quantum Cosmology · Physics 2024-08-07 Piyali Bhar

We investigate a new type of Schwarzschild wormhole, which relies on a 3-dimensional spacetime defect with degenerate metrics. This particular wormhole is a solution of the vacuum Einstein equations. We also study the generalized…

General Relativity and Quantum Cosmology · Physics 2023-07-11 Zi-Liang Wang

There are a number of reasons to study wormholes with generic cosmological constant $\Lambda$. Recent observations indicate that present accelerating expansion of the universe demands $\Lambda>0$. On the other hand, some extended theories…

General Relativity and Quantum Cosmology · Physics 2015-11-24 Y. Heydarzade , N. Riazi , H. Moradpour

In this paper, we obtain new $d$-dimensional and asymptotically flat wormhole solutions by assuming a specific form of the energy density distribution. This is addressed by considering the generalization of the so-called Dymnikova model,…

General Relativity and Quantum Cosmology · Physics 2023-03-29 Milko Estrada , Celio R. Muniz

This brief review discusses the existence conditions of wormhole throats and wormholes as global configurations in general relativity under the assumptions of cylindrical and axial symmetries. It is pointed out, in particular, that wormhole…

General Relativity and Quantum Cosmology · Physics 2015-09-07 K. A. Bronnikov , M. V. Skvortsova

Traversible wormhole space-times are found as static, spherically symmetric solutions to the Einstein equations with ingoing and outgoing pure ghost radiation, i.e. pure radiation with negative energy density. Switching off the radiation…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Sean A. Hayward

The massless conformally coupled scalar field is characterized by the so-called "new improved stress-energy tensor", which is capable of classically violating the null energy condition. When coupled to Einstein gravity we find a…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Carlos Barcelo , Matt Visser

We prove the impossibility of cylindrical thin-shell wormholes supported by matter satisfying the energy conditions everywhere, under reasonable assumptions about the asymptotic behaviour of the - in general different - metrics at each side…

General Relativity and Quantum Cosmology · Physics 2012-03-19 Claudio Simeone

It was shown by Ford and Roman in 1996 that quantum field theory severely constrains wormhole geometries on a macroscopic scale. The first part of this paper discusses a wide class of wormhole solutions that meet these constraints. The type…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Peter K. F. Kuhfittig

A new class of solutions which yields an $(n+1)$-dimensional spacetime with a longitudinal nonlinear magnetic field is introduced. These spacetimes have no curvature singularity and no horizon, and the magnetic field is non singular in the…

High Energy Physics - Theory · Physics 2009-08-05 M. H. Dehghani , S. H. Hendi

Wormholes are tunnels connecting two different points in space-time. In Einstein's General Relativity theory, wormholes are expected to be filled by exotic matter, i.e., matter that does not satisfy the energy conditions and may have…

General Relativity and Quantum Cosmology · Physics 2018-01-17 P. H. R. S. Moraes , P. K. Sahoo

To explain Gamma Ray Bursts, Ruffini argued that the event horizon of a charged black hole is surrounded by a special region called, the Dyadosphere where electric field exceeds the critical value for $e^+$ $e^-$ pair production. In the…

General Relativity and Quantum Cosmology · Physics 2009-02-10 F. Rahaman , M. Kalam , K A Rahman

Vacuum static, axially symmetric space-times in $D$-dimensional general relativity with a Ricci-flat internal space are discussed. It is shown, in particular, that some of the monopole-type solutions are free of curvature singularities and…

General Relativity and Quantum Cosmology · Physics 2007-05-23 K. A. Bronnikov , V. N. Melnikov
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