English
Related papers

Related papers: Star-plus-wormhole systems with two interacting sc…

200 papers

We consider a self-consistent Einstein-Maxwell-Kalb-Ramond system in the bulk D=4 space-time interacting with a variable-tension electrically charged lightlike brane. The latter serves both as a material and charge source for gravity and…

High Energy Physics - Theory · Physics 2011-09-27 Eduardo Guendelman , Alexander Kaganovich , Emil Nissimov , Svetlana Pacheva

Given an anisotropic fluid source, we determine in closed forms, upon solving the field equations of general relativity (GR) and teleparallel gravity (TEGR) coupled to a cosmological constant, cylindrically symmetric four-dimensional…

General Relativity and Quantum Cosmology · Physics 2021-03-17 Mustapha Azreg-Aïnou

Wormholes are tunnels connecting different regions in space-time. They were obtained originally as a solution for Einstein's General Relativity theory and according to this theory they need to be filled by an exotic kind of anisotropic…

General Relativity and Quantum Cosmology · Physics 2019-01-15 P. K. Sahoo , P. H. R. S. Moraes , Parbati Sahoo , G. Ribeiro

We cut a general, static, spherically symmetric spacetime and paste its copy to make a wormhole with a thin shell of any barotropic fluid in general relativity. We show that the stability of the thin-shell wormhole is characterized by a set…

General Relativity and Quantum Cosmology · Physics 2024-01-30 Naoki Tsukamoto , Takafumi Kokubu

We consider static spherically symmetric solutions in the scalar-tensor theory of gravity with a scalar field possessing the nonminimal kinetic coupling to the curvature. The lagrangian of the theory contains the term $(\varepsilon…

General Relativity and Quantum Cosmology · Physics 2015-06-22 R. V. Korolev , Sergey V. Sushkov

We present a new class of solutions for static spherically symmetric wormhole spacetimes in conformal gravity and outline a detailed method for their construction. As an explicit example, we construct a class of traversable and…

General Relativity and Quantum Cosmology · Physics 2018-10-09 Manuel Hohmann , Christian Pfeifer , Martti Raidal , Hardi Veermäe

We have found a simple exact solution of spherically-symmetrical Einstein equations describing a wormhole for an inhomogeneous distribution of the phantom energy. The equation of state is linear but highly anisotropic: while the radial…

General Relativity and Quantum Cosmology · Physics 2009-11-11 O. B. Zaslavskii

We consider anisotropic cosmological models with an universe of dimension 4 or more, factorized into n>1 Ricci-flat spaces, containing an m-component perfect fluid of m non-interacting homogeneous minimally coupled scalar fields under…

General Relativity and Quantum Cosmology · Physics 2015-06-25 U. Kasper , M. Rainer , A. Zhuk

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

A possible candidate for the present accelerated expansion of the Universe is ''phantom energy'', which possesses an equation of state of the form $\omega\equiv p/\rho<-1$, consequently violating the null energy condition. As this is the…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Francisco S. N. Lobo

In this work, we explore wormhole solutions in $f(R,T)$ theory of gravity, where $R$ is the scalar curvature and $T$ is the trace of stress-energy tensor of matter. To investigate this, we consider static spherically symmetric geometry with…

General Relativity and Quantum Cosmology · Physics 2016-08-10 M. Zubair , Saira Waheed , Yasir Ahmad

We investigate relativistic spherically symmetric static perfect fluid models in the framework of the theory of dynamical systems. The field equations are recast into a regular dynamical system on a 3-dimensional compact state space,…

General Relativity and Quantum Cosmology · Physics 2009-11-10 J. Mark Heinzle , N. Rohr , C. Uggla

The gargantuan discrepancy between the value of the observed cosmological constant and that expected from the zero-point energy of known matter fields can be eliminated by supposing that on macroscopic scales the overwhelming majority of…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Enrico Rodrigo

Recently, a modified theory of gravity was presented, which consists of the superposition of the metric Einstein-Hilbert Lagrangian with an $f(\cal R)$ term constructed \`{a} la Palatini. The theory possesses extremely interesting features…

General Relativity and Quantum Cosmology · Physics 2012-12-20 Salvatore Capozziello , Tiberiu Harko , Tomi S. Koivisto , Francisco S. N. Lobo , Gonzalo J. Olmo

We study geodesic motion near the throats of asymptotically flat, static, spherically~symmetric traversable wormholes supported by a self-gravitating minimally coupled phantom scalar field with an arbitrary self-interaction potential. We…

General Relativity and Quantum Cosmology · Physics 2020-10-20 Ivan Potashov , Julia Tchemarina , Alexander Tsirulev

In this study, we explore a topologically charged higher-dimensional traversable defect wormhole, with a specific emphasis on five dimensions. Particularly noteworthy is the fact that the matter-energy distribution attributed to this…

General Relativity and Quantum Cosmology · Physics 2024-08-06 Faizuddin Ahmed

We construct a static axisymmetric wormhole from the gravitational field of two charged shells which are kept in equilibrium by their electromagnetic repulsion. For large separations the exterior tends to the Majumdar-Papapetrou spacetime…

General Relativity and Quantum Cosmology · Physics 2009-10-28 F. Schein , P. C. Aichelburg

Recently, the ring images or the shadow images of the centers of the galaxy M87 and the Milky way have been reported by Event Horizon Telescope Collaboration. It is believed that the ring images imply that the central objects form unstable…

General Relativity and Quantum Cosmology · Physics 2025-02-11 Naoki Tsukamoto

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 explore the possibility of traversable wormhole formation in the dark matter halos in the context of $f(Q)$ gravity. We obtain the exact wormhole solutions with anisotropic matter source based on the Bose-Einstein condensate,…

General Relativity and Quantum Cosmology · Physics 2024-10-28 G. Mustafa , Zinnat Hassan , P. K. Sahoo