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Related papers: Wormholes and the imaginary distance bound

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A self--sustained traversable wormhole is obtained as a vacuum solution of a scale-dependent gravitational theory. Comparison with other approaches towards wormhole self--sustainability are presented, with emphasis on the running of the…

General Relativity and Quantum Cosmology · Physics 2019-04-01 Ernesto Contreras , Pedro Bargueño

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

There are some gravitational theories in which the ordinary energy-momentum conservation law is not valid in the curved spacetime. Rastall gravity is one of the known theories in this regard which includes a non-minimal coupling between…

General Relativity and Quantum Cosmology · Physics 2018-04-17 H. Moradpour , N. Sadeghnezhad , S. H. Hendi

We construct wormholes in Einstein-vector-Gauss-Bonnet theory where a real massless vector field is coupled to the higher curvature Gauss-Bonnet invariant. We consider three coupling functions which depend on the square of the vector field.…

General Relativity and Quantum Cosmology · Physics 2022-09-28 Simon Barton , Claus Kiefer , Burkhard Kleihaus , Jutta Kunz

The massless conformally coupled scalar field is characterized by the so-called "new improved stress-energy tensor", which is capable of classically violating the null energy condition. When coupled to Einstein gravity we find a…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Carlos Barcelo , Matt Visser

Wormholes are hypothetical tunnels that connect remote parts of spacetime. In General Relativity, wormholes are threaded by exotic matter that violates the energy conditions. In this work, we consider wormholes threaded by nonexotic matter…

General Relativity and Quantum Cosmology · Physics 2019-06-26 Rui-Hui Lin , Zhen-Yuan Wu , Xiang-Hua Zhai

In this work, we find novel static and spherically symmetric wormhole geometries using a three-form field. By solving the gravitational field equations, we find a variety of analytical and numerical solutions and show that it is possible…

General Relativity and Quantum Cosmology · Physics 2018-08-10 Bruno J. Barros , Francisco S. N. Lobo

A lower bound on the size of a Lorentzian wormhole can be obtained by semiclassically introducing the Planck cut-off on the magnitude of tidal forces (Horowitz-Ross constraint). Also, an upper bound is provided by the quantum field…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Kamal Kanti Nandi , Yuan-Zhong Zhang , K. B. Vijaya Kumar

Motivated by the early discovery of the gigantic landscape of string theory vacua, in recent years people switched direction to try to find constraints on low energy effective field theories from UV-complete descriptions for example quantum…

High Energy Physics - Theory · Physics 2020-02-28 Hao Geng

A generalisation of the asymptotic wormhole boundary condition for the case of spacetimes with a cosmological horizon is proposed. In particular, we consider de Sitter spacetime with small cosmological constant. The wave functions selected…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Carlos Barcelo

A gravitational scenario is proposed where the euclidean action is invariant under the isotropic and homogeneous version of the euclidean {\it U(1)} group of local transformations of the scale factor and scalar matter field, interpreting…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Pedro F. Gonzalez-Diaz

We consider novel wormhole solutions supported by a matter content that minimally violates the null energy condition. More specifically, we consider an equation of state in which the sum of the energy density and radial pressure is…

General Relativity and Quantum Cosmology · Physics 2014-11-10 Mariam Bouhmadi-Lopez , Francisco S. N. Lobo , Prado Martin-Moruno

It has been suggested that the cosmological constant is a variable dynamical quantity. A class of solution has been presented for the spherically symmetric space time describing wormholes by assuming the erstwhile cosmological constant…

General Relativity and Quantum Cosmology · Physics 2008-11-26 F. Rahaman , M. Kalam , M. Sarker , A. Ghosh , B. Raychaudhuri

We construct a static axisymmetric wormhole from the gravitational field of two Schwarzschild particles which are kept in equilibrium by strings (ropes) extending to infinity. The wormhole is obtained by matching two three-dimensional…

General Relativity and Quantum Cosmology · Physics 2014-11-17 F. Schein , P. C. Aichelburg , W. Israel

The detailed numerical and analytical approximate analysis of wormhole-like solutions in 5D Kaluza-Klein gravity is given. It is shown that some part of these solutions with $E \approx H, E>H$ relation between electric $E$ and magnetic $H$…

General Relativity and Quantum Cosmology · Physics 2007-05-23 V. Dzhunushaliev

On the basis of exact solutions to the Einstein-Abelian gauge-dilaton equations in $D$-dimensional gravity, the properties of static axial configurations are discussed. Solutions free of curvature singularities are selected; they can be…

General Relativity and Quantum Cosmology · Physics 2009-10-28 Kirill A. Bronnikov , Julio C. Fabris

Based on the rigid positive energy theorem we proved the uniqueness of static spherically symmetric traversable wormholes with two asymptotically flat ends, being the higher-dimensional solutions of Einstein scalar phantom field. The proof…

High Energy Physics - Theory · Physics 2018-02-14 Marek Rogatko

Continuous global symmetries are expected to be broken by gravity, which can lead to important phenomenological consequences. A prime example is the threat that this poses to the viability of the Peccei-Quinn solution to the strong CP…

High Energy Physics - Phenomenology · Physics 2021-01-12 James Alvey , Miguel Escudero

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

In this paper we present a new family of wormhole geometries in Lovelock theories with a unique vacuum, and study their stability under scalar field perturbations. As the solutions already known in the literature for Chern-Simons gravity on…

High Energy Physics - Theory · Physics 2024-07-02 Octavio Fierro , Daniela Narbona , Julio Oliva , Constanza Quijada , Guillermo Rubilar