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Related papers: Macroscopic wormholes in noncommutative geometry

200 papers

We have proposed a novel shape function on which the metric that models traversable wormholes is dependent. Using this shape function, the energy conditions, equation of state and anisotropy parameter are analyzed in $f(R)$ gravity,…

General Relativity and Quantum Cosmology · Physics 2020-05-19 Gauranga C. Samanta , Nisha Godani , Kazuharu Bamba

In this paper we study the possibility of sustaining an evolving wormhole via exotic matter made out of phantom energy. We show that this exotic source can support the existence of evolving wormhole spacetimes. Explicitly, a family of…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Mauricio Cataldo , Pedro Labrana , Sergio del Campo , Juan Crisostomo , Patricio Salgado

In this paper, we evaluate traversable wormhole solutions through Karmarkar condition in $f(R,T)$ theory, where $T$ is the trace of the energy-momentum tensor and $R$ represents the Ricci scalar. We develop a wormhole shape function for the…

General Relativity and Quantum Cosmology · Physics 2023-03-06 M. Sharif , Arooj Fatima

The well-known problem of wormholes in general relativity (GR) is the necessity of exotic matter, violating the Weak Energy Condition (WEC), for their support. This problem looks easier if, instead of island-like configurations, one…

General Relativity and Quantum Cosmology · Physics 2020-01-08 K. A. Bronnikov , S. V. Bolokhov , M. V. Skvortsova

In this work we wonder if there is a way to generate a wormhole (WH) in nature using "normal" matter. In order to give a first answer to this question, we study a massless scalar field coupled to an electromagnetic one (dilatonic field)…

General Relativity and Quantum Cosmology · Physics 2021-02-09 Tonatiuh Matos , Galaxia Miranda

We describe new configurations of electromagnetic (EM) material parameters, the electric permittivity $\epsilon$ and magnetic permeability $\mu$, that allow one to construct from metamaterials objects that function as invisible tunnels.…

Mathematical Physics · Physics 2008-11-26 Allan Greenleaf , Yaroslav Kurylev , Matti Lassas , Gunther Uhlmann

Some novel regular spacetimes are considered that show a non-stationary wormhole structure. A Simpson-Visser-like procedure is applied to reconstruct these regular spacetimes, free of time-like and space-like singularities. Such a procedure…

General Relativity and Quantum Cosmology · Physics 2025-08-13 G. Alencar , R. Dárlla , Shin'ichi Nojiri , Sergei D. Odintsov , Diego Sáez-Chillón Gómez

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

It is a very well known fact that the energy conditions concerning traversable wormhole (WH) solutions of Einstein equations are violated. Consequently, attempts to avoid the violation of the energy conditions constitutes one of the main…

General Relativity and Quantum Cosmology · Physics 2014-04-14 Everton M. C. Abreu , Nélio Sasaki

The existing solutions to the Einstein equations describing rotating cylindrical wormholes are not asymptotically flat and therefore cannot describe wormhole entrances as local objects in our Universe. To overcome this difficulty, flat…

General Relativity and Quantum Cosmology · Physics 2016-03-30 K. A. Bronnikov

In this short review we present some recently obtained traversable wormhole models in the framework of general relativity (GR) in four and six dimensions that somehow widen our common ideas on wormhole existence and properties. These are,…

General Relativity and Quantum Cosmology · Physics 2022-03-23 K. A. Bronnikov

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

The existence of even the simplest magnetized wormholes may lead to observable consequences. In the case where both the wormhole and the magnetic field around its mouths are static and spherically symmetric, and gas in the region near the…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-01 Mikhail Piotrovich , Serguei Krasnikov , Stanislava Buliga , Tinatin Natsvlishvili

This paper explores static wormhole solutions in f(Q,T) theory, where Q is the non-metricity and T is the trace of energy-momentum tensor. We derive the field equations that describe gravitational phenomena in the existence of non-metricity…

General Relativity and Quantum Cosmology · Physics 2024-11-07 M. Zeeshan Gul , M. Sharif , Shajee Shahid , Faisal Javed

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

Wormhole solutions in classical General Relativity are unstable and hence non traversable. Morris and Thorne discovered a traversable wormhole solution that required the energy momentum tensor of matter sources to violate various energy…

General Relativity and Quantum Cosmology · Physics 2019-10-21 Anshuman Baruah , Atri Deshamukhya

We briefly discuss some of the known and new properties of rotating geometries that are relevant to this work. We generalize the analytical method of superposition of fields, known for generating nonrotating solutions, and apply it to…

General Relativity and Quantum Cosmology · Physics 2016-01-07 Mustapha Azreg-Aïnou

In this paper, we introduce higher dimensional thin-shell wormholes in pure Gauss-Bonnet gravity. The focus is on thin-shell wormholes constructed by $N\geq5$-dimensional spherically symmetric vacuum solutions. The results suggest that,…

General Relativity and Quantum Cosmology · Physics 2020-11-25 S. Danial Forghani , S. Habib Mazharimousavi

For a generic $f(R)$ which admits a polynomial expansion of at least third order (i.e. $\frac{d^{3}f}{dR^{3}}\neq 0$) we find the near-throat wormhole solution. Necessary conditions for the existence of wormholes in such $f(R)$ theories are…

General Relativity and Quantum Cosmology · Physics 2016-11-15 S. Habib Mazharimousavi , M. Halilsoy

We describe a class of wormholes that generically become traversable after incorporating gravitational back-reaction from linear quantum fields satisfying appropriate (periodic or anti-periodic) boundary conditions around a non-contractible…

High Energy Physics - Theory · Physics 2019-08-12 Zicao Fu , Brianna Grado-White , Donald Marolf