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Related papers: Macroscopic wormholes in noncommutative geometry

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We study the Lorentzian static traversable wormholes coupled to quadratic scalar fields. We also obtain the solutions of the scalar fields and matters in the wormhole background and find that the minimal size of the wormhole should be…

General Relativity and Quantum Cosmology · Physics 2009-10-31 S. -W. Kim , S. P. Kim

This paper generalizes two of the author's earlier wormhole solutions that are characterized by an extra spatial dimension. This paper adds the assumption that the components of the line element are functions not only of the radial…

General Relativity and Quantum Cosmology · Physics 2025-06-17 Peter K. F. Kuhfittig

We argue that a microscopic structure for space-time such as that expected in a quantum foam scenario, in which microscopic wormholes and other topological structures should play a relevant role, might lead to an effective metric-affine…

High Energy Physics - Theory · Physics 2015-06-15 Francisco S. N. Lobo , Gonzalo J. Olmo , D. Rubiera-Garcia

We present the general method of constructing curved traversable wormholes in (3+1)-d spacetime and proceed to thoroughly discuss the physics of a zero tidal force metric without cross-terms. The (3+1)-d solution is compared with the…

General Relativity and Quantum Cosmology · Physics 2014-04-18 Vee-Liem Saw , Lock Yue Chew

Traversable wormhole are primarily useful as "gedanken-experiments" and as a theoretician's probe of the foundations of general relativity. In this work, we analyse the possibility of having tunnels in a hyperbolic spacetime. We obtain…

General Relativity and Quantum Cosmology · Physics 2010-09-02 Francisco S. N. Lobo , José P. Mimoso

We consider static and spherically symmetric wormhole solutions in extended metric-affine theories of gravity supposing that stability and traversability of these objects can be achieved by means of the geometric degrees of freedom. In…

General Relativity and Quantum Cosmology · Physics 2023-11-17 Vittorio De Falco , Salvatore Capozziello

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

It has been argued that wormholes are as good a prediction of Einstein's theory as black holes but the theoretical construction requires a reverse strategy, specifying the desired geometric properties of the wormhole and leaving open the…

General Relativity and Quantum Cosmology · Physics 2017-02-15 Peter K. F. Kuhfittig

In this paper we study traversable wormholes in the context of $f(R)$ gravity. Exact solutions of traversable wormholes are found by imposing the nonconstant Ricci scalar. These solutions asymptotically match spherical, flat and hyperbolic…

General Relativity and Quantum Cosmology · Physics 2019-10-23 Hanif Golchin , Mohammad Reza Mehdizadeh

In this work, we undertake an analysis of new wormhole solutions within an action-dependent Lagrangian framework. These geometries can be traversable and supported by a positive energy density. The modification of the gravitational field…

General Relativity and Quantum Cosmology · Physics 2024-06-12 Ismael Ayuso , Ruth Lazkoz

The current interests in the universe motivate us to go beyond Einstein's General theory of relativity. One of the interesting proposals comes from a new class of teleparallel gravity named symmetric teleparallel gravity, i.e., $f(Q)$…

General Relativity and Quantum Cosmology · Physics 2021-06-09 Zinnat Hassan , Sanjay Mandal , P. K. Sahoo

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

We consider Non-local Gravity in view to obtain stable and traversable wormhole solutions. In particular, the class of Non-local Integral Kernel Theories of Gravity, with the inverse d'Alembert operator in the gravitational action, is taken…

General Relativity and Quantum Cosmology · Physics 2022-11-28 Salvatore Capozziello , Nisha Godani

We construct thin-shell electrically charged wormholes in d-dimensional general relativity with a cosmological constant. The wormholes constructed can have different throat geometries, namely, spherical, planar and hyperbolic. Unlike the…

General Relativity and Quantum Cosmology · Physics 2018-12-05 Gonçalo A. S. Dias , José P. S. Lemos

A fundamental property in wormhole physics is the flaring-out condition of the throat, which through the Einstein field equation entails the violation of the null energy condition. In the context of modified theories of gravity, it has also…

General Relativity and Quantum Cosmology · Physics 2012-11-07 Francisco S. N. Lobo

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

Generalizing of the Maxwell field to nonlinear electrodynamics theories, we look for the magnetic solutions. In initial approximation these models give the usual linear electrodynamics. We consider a suitable metric and investigate the…

General Physics · Physics 2014-05-28 S. H. Hendi

Recent studies have shown that (a) quantum effects may be sufficient to support a wormhole throat and (b) the total amount of "exotic matter" can be made arbitrarily small. Unfortunately, using only small amounts of exotic matter may result…

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

It has been suggested that a possible candidate for the present accelerated expansion of the Universe is ''phantom energy''. The latter possesses an equation of state of the form $\omega\equiv p/\rho<-1$, consequently violating the null…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Francisco S. N. Lobo

The presence of exotic matter for the existence of the wormhole geometry has been an unavoidable problem in GR. In recent studies researchers have tried to deal with this issue using modified gravity theories where the WH geometry is…

General Physics · Physics 2022-04-19 Umesh Kumar Sharma , Shweta , Ambuj Kumar Mishra