English
Related papers

Related papers: Light Dragging Phenomenon and Expanding Wormholes

200 papers

The present paper is intended for studying the effect of strong gravitational lensing in the context of charged wormhole. To study this effect, the conditions determining the existence of photon spheres at and outside the throat are…

General Relativity and Quantum Cosmology · Physics 2021-06-02 Nisha Godani , Gauranga C. Samanta

In this work we study and compare the features of gravitational entropy near the throat of transversable wormholes formed by exotic matter and wormholes in galactic halos. We have verified that gravitational entropy and entropy density of…

General Relativity and Quantum Cosmology · Physics 2020-03-19 R. de C. Lima , José A. C. Nogales , S. H. Pereira

We reformulate the construction of wormhole solutions as perturbations around near-horizon geometries of near-extremal Reissner-Nordstr\"{o}m black holes in four dimensions and equal-angular-momenta Myers-Perry black holes in five…

General Relativity and Quantum Cosmology · Physics 2025-11-27 Takamasa Kanai , Kengo Maeda , Daisuke Yoshida

It has been speculated that Lorentzian wormholes of the Morris- Thorne type might be allowed by the laws of physics at submicroscopic, e.g. Planck, scales and that a sufficiently advanced civilization might be able to enlarge them to…

General Relativity and Quantum Cosmology · Physics 2009-10-22 Thomas A. Roman

Wormholes are speculative structures linking disparate space-time points. Their geometry can be obtained by solving Einstein equations with tolerating the violation of null energy conditions. Recently, many researchers have studied…

General Relativity and Quantum Cosmology · Physics 2022-03-10 J. Sadeghi , B. Pourhassan , S. Noori Gashti , S. Upadhyay

In this paper, we theoretically investigate gravitational lensing within the space-time framework of traversable wormholes, focusing on the combined effects of a global monopole and a cosmic string. Specifically, we examine the…

General Relativity and Quantum Cosmology · Physics 2025-04-21 Faizuddin Ahmed , İzzet Sakallı , Ahmad Al-Badawi

A radial deformation of the Kerr metric is studied which leads to the appearance of wormholes in certain cases. {\bf These wormholes can be thought of as being formed by two distinct but identical asymptotically non-flat spacetimes joined…

General Relativity and Quantum Cosmology · Physics 2014-07-17 T. Ghasabi , N. Riazi

Within general relativity, we determine the energy conditions needed for the existence of a toroidal $T^2$ wormhole. For this purpose, we employ the conditions of the positiveness of the second derivatives of the relevant components of the…

General Relativity and Quantum Cosmology · Physics 2019-10-16 Vladimir Dzhunushaliev , Vladimir Folomeev , Burkhard Kleihaus , Jutta Kunz

Renormalized vacuum expectation values of electromagnetic stress-energy tensor are calculated in the background spherically-symmetrical metric of the wormhole's topology. Covariant geodesic point separation method of regularization is used.…

General Relativity and Quantum Cosmology · Physics 2009-10-22 V. Khatsymovsky

We consider a class of stationary and axisymmetric wormhole spacetimes that is closely related to, but not identical with, the class of Teo wormholes. We fix a point $p$ (observation event) and a timelike curve $\gamma$ (worldline of a…

General Relativity and Quantum Cosmology · Physics 2022-01-11 Mourad Halla , Volker Perlick

Although wormholes can be treated as topological objects in spacetime and from a global point-of-view, a precise definition of what a wormhole throat is and where it can be located can be developed and treated entirely in terms of local…

General Relativity and Quantum Cosmology · Physics 2007-05-23 David Hochberg , Matt Visser

Following the recent theory of Lovelock-Brans-Dicke gravity, we continue to investigate the conditions to support traversable wormholes by the gravitational effects of spacetime parity and topology, which arise from the nonminimal couplings…

General Relativity and Quantum Cosmology · Physics 2016-01-08 David Wenjie Tian

Two spherically symmetric, static Lorentzian wormholes are obtained in tetrad theory of gravitation as a solution of the equation $\rho=\rho_t=0$, where $\rho=T_{ij}u^iu^j, \rho_t=(T_{ij}-{1/2}Tg_{ij})u^iu^j$ and $u^iu_i=-1$. This equation…

General Relativity and Quantum Cosmology · Physics 2009-09-24 Gamal Gergess Lamee Nashed

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

Traversable wormhole solutions are explored in $f(\mathcal{R},\mathbb{T})$ gravity, a curvature--matter extension in which $\mathcal{R}$ is the Ricci scalar and $\mathbb{T}$ denotes the trace of the energy--momentum tensor. To generate…

General Relativity and Quantum Cosmology · Physics 2026-02-02 G. G. L. Nashed , A. Eid

Wormhole geometries in curvature-matter coupled modified gravity are explored, by considering an explicit nonminimal coupling between an arbitrary function of the scalar curvature, R, and the Lagrangian density of matter. It is the…

General Relativity and Quantum Cosmology · Physics 2010-11-09 Nadiezhda Montelongo Garcia , Francisco S. N. Lobo

The self-interaction for a static point charge in the space-time of a thin-shell wormhole constructed connecting two identical Schwarzschild geometries is calculated in a series expansion. The electrostatic self-force is evaluated…

General Relativity and Quantum Cosmology · Physics 2015-06-17 E. Rubín de Celis , O. P. Santillán , C. Simeone

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

Natural wormholes and its astrophysical signatures have been sugested in various oportunities. By applying the strong field limit of gravitational lensing theory, we calculate the deflection angle and magnification curves produced by…

General Relativity and Quantum Cosmology · Physics 2022-06-08 J. M. Tejeiro , E. Larranaga

In [J. Blazquez-Salcedo, C. Knoll, E. Radu, Phys. Rev. Lett. 126 (2021) no.10, 101102] asymptotically flat traversable wormhole solutions were obtained in the Einstein-Dirac-Maxwell theory without using phantom matter. The normalizable…

General Relativity and Quantum Cosmology · Physics 2022-03-07 R. A. Konoplya , A. Zhidenko
‹ Prev 1 3 4 5 6 7 10 Next ›