English
Related papers

Related papers: Macroscopic wormholes in noncommutative geometry

200 papers

Traversability in relation with tides across thin-shell wormholes is analyzed. Conditions for a safe travel through a wormhole throat are established in terms of the parameters characterizing the geometries and reasonable assumptions…

General Relativity and Quantum Cosmology · Physics 2021-11-02 E. Rubín de Celis , C. Simeone

We present a traversable-wormhole solution of the gravitational field equation of General Relativity without need of exotic matter (exotic matter can, for example, have negative energy density and vanishing isotropic pressure). Instead of…

General Relativity and Quantum Cosmology · Physics 2023-06-16 F. R. Klinkhamer

Wormholes are non-trivial topological structures that arise as exact solutions to Einstein's field equations, theoretically connecting distinct regions of spacetime via a throat-like geometry. While static traversable wormholes necessarily…

General Relativity and Quantum Cosmology · Physics 2025-07-22 Mahdi Kord Zangeneh , Francisco S. N. Lobo

We consider stationary, cylindrically symmetric configurations in general relativity and formulate necessary conditions for the existence of rotating cylindrical wormholes. It is shown that in a comoving reference frame the rotational part…

General Relativity and Quantum Cosmology · Physics 2013-09-12 Kirill A. Bronnikov , Vladimir G. Krechet , José P. S. Lemos

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

High Energy Physics - Theory · Physics 2012-08-01 Everton M. C. Abreu , Nélio Sasaki

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

An attempt has been made to have an analytical description for possible traversable wormhole in non-static spherically symmetric space-time supported by anisotropic fluid. Both trivial and non-trivial choices of the red-shift function…

General Relativity and Quantum Cosmology · Physics 2024-09-04 Subenoy Chakraborty , Madhukrishna Chakraborty

In this article, we study the possibility of sustaining a static and spherically symmetric traversable wormhole geometries admitting conformal motion in Einstein gravity, which presents a more systematic approach to search a relation…

General Relativity and Quantum Cosmology · Physics 2017-02-01 Piyali Bhar , Farook Rahaman , Tuhina Manna , Ayan Banerjee

A fundamental ingredient in wormhole physics is the presence of exotic matter, which involves the violation of the null energy condition. Although a plethora of wormhole solutions have been explored in the literature, it is useful to find…

General Relativity and Quantum Cosmology · Physics 2012-07-19 Francisco S. N. Lobo

In this work, we construct traversable wormhole geometries in the context of f(R) modified theories of gravity. We impose that the matter threading the wormhole satisfies the energy conditions, so that it is the effective stress-energy…

General Relativity and Quantum Cosmology · Physics 2009-11-12 Francisco S. N. Lobo , Miguel A. Oliveira

This paper examines wormhole geometries in the context of $f(Q,T)$ gravity under the background of non-commutative distributions. We discuss the analytical solutions assuming spherical symmetry and the presence of conformal Killing vectors,…

General Relativity and Quantum Cosmology · Physics 2024-03-22 Moreshwar Tayde , Zinnat Hassan , P. K. Sahoo

We study the geometry of a wormhole spacetime filled with anisotropic matter in the context of general relativity. In the course of the study, new static and spherically symmetric solutions, analytic and numerical ones, are found. We…

General Relativity and Quantum Cosmology · Physics 2019-09-04 Hyeong-Chan Kim , Youngone Lee

It was argued in literature that traversable wormholes can exist with arbitrarily small violation of null energy conditions. We show that if the amount of exotic material near the wormhole throat tends to zero, either this leads to a horn…

General Relativity and Quantum Cosmology · Physics 2008-11-26 O. B. Zaslavskii

In this paper we seek a relationship between the assumption of conformal symmetry and the exotic matter needed to hold a wormhole open. By starting with a Morris-Thorne wormhole having a constant energy density, it is shown that the…

General Relativity and Quantum Cosmology · Physics 2024-02-20 Peter K. F. Kuhfittig

Recent papers by Fewster and Roman have emphasized that wormholes supported by arbitrarily small amounts of exotic matter will have to be incredibly fine-tuned if they are to be traversable. This paper discusses a wormhole model that…

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

Wormholes that meet the flare-out condition violate the weak energy condition in classical general relativity. The purpose of this note is to show that even a slight modification of the gravitational theory could, under certain conditions,…

General Relativity and Quantum Cosmology · Physics 2017-02-03 Peter K. F. Kuhfittig

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

This paper discusses traversable wormholes that differ slightly but significantly from those of the Morris-Thorne type under the assumption of cylindrical symmetry. The throat is a piecewise smooth cylindrical surface resulting in a shape…

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

We present here analytical solutions of General Relativity that describe evolving wormholes with a non-constant redshift function. We show that the matter that threads these wormholes is not necessarily exotic. Finally, we investigate some…

General Relativity and Quantum Cosmology · Physics 2009-10-30 Luis A. Anchordoqui , Diego F. Torres , Marta L. Trobo , Santiago E. Perez Bergliaffa

This paper generalizes the static and spherically symmetric traversable wormhole geometry to a rotating axially symmetric one with a time-dependent angular velocity by means of an exact solution. It was found that the violation of the weak…

General Relativity and Quantum Cosmology · Physics 2010-11-19 Peter K. F. Kuhfittig