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Related papers: Wormholes minimally violating the null energy cond…

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In this work, wormholes, tunnel like structures introduced by Morris \& Thorne \cite{Morris95}, are explored within the framework of $f(R)$ gravity. Using the shape function $b(r)=r_0\big(\frac{r}{r_0}\big)^\gamma$, where $0<\gamma<1$, and…

General Relativity and Quantum Cosmology · Physics 2019-08-14 Gauranga C Samanta , Nisha Godani

In the present paper we discuss properties of a model of a ring wormhole, recently proposed by Gibbons and Volkov. Such a wormhole connects two flat spacetimes which are glued through discs of the radius $a$ bounded by the string with…

High Energy Physics - Theory · Physics 2023-07-26 Valeri P. Frolov , Pavel Krtous , Andrei Zelnikov

To find more deliberate $f(R, T)$ astrophysical solutions, we proceed by studying wormhole geometries under the assumption of spherical symmetry and the existence of a conformal Killing symmetry to attain the more acceptable astrophysical…

General Relativity and Quantum Cosmology · Physics 2020-08-21 Ayan Banerjee , Ksh. Newton Singh , M. K. Jasim , Farook Rahaman

In 6D general relativity with a scalar field as a source of gravity, a new type of static wormhole solutions is presented: such wormholes connect our universe with a small 2D extra subspace with a universe where this extra subspace is…

General Relativity and Quantum Cosmology · Physics 2016-12-07 K. A. Bronnikov , M. V. Skvortsova

We consider a static spherically symmetric thin shell wormhole collides with another thin shell consisting of ordinary matter. By employing the geometrical constraint, which leads to the conservation of energy and momentum, we show that the…

General Relativity and Quantum Cosmology · Physics 2016-03-23 Sijie Gao , Xiaobao Wang

We use a combination of numerical and analytical methods, exploiting the equations derived in a preceding paper, to classify all spherically symmetric self-similar solutions which are asymptotically Friedmann at large distances and contain…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Hideki Maeda , Tomohiro Harada , B. J. Carr

Wormholes (WHs) are considered as hypothetical shortcuts or tunnels in spacetime. In general relativity (GR), the fundamental ingredient of WH geometry is the presence of exotic matter at the throat, which is responsible for the violation…

General Relativity and Quantum Cosmology · Physics 2020-02-19 Parbati Sahoo , Annika Kirschner , P. K. Sahoo

Since the general relativistic approach requires exotic matter with negative energy density, constructing wormholes containing realistic matter is a crucial challenge. Therefore, extending General Relativity to non-minimal cases may be an…

General Relativity and Quantum Cosmology · Physics 2024-08-15 Özcan Sert

The study of traversable wormholes is very hot topic for the past 30 years. One of the best possible way to make traversable wormhole is using the thin-shells to cut and paste two spacetime which has tunnel from one region of space-time to…

General Relativity and Quantum Cosmology · Physics 2016-10-27 Ali Övgün

A phase space is built that allows to study, classify and compare easily large classes of static spherically symmetric wormholes solutions, sustained by an isotropic perfect fluid in General Relativity. We determine the possible locations…

General Relativity and Quantum Cosmology · Physics 2020-01-01 Stephane Fay

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

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

It has been suggested that a possible candidate for the present accelerated expansion of the Universe is ''phantom energy''. The latter possesses an equation of state of the form $\omega\equiv p/\rho<-1$, consequently violating the null…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Francisco S. N. Lobo

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

The possibility of static and spherically symmetric traversable wormhole solution in modified teleparallel Rastall gravity (MTRG) in a non-diagonal tetrad is investigated. Rastall assumption modifies the field equations and energy-momentum…

General Relativity and Quantum Cosmology · Physics 2023-03-15 N. Nazavari , Kh. Saaidi , Abolhassan Mohammadi

In this paper, we explore higher-dimensional asymptotically flat wormhole geometries in the framework of Gauss-Bonnet (GB) gravity and investigate the effects of the GB term, by considering a specific radial-dependent redshift function and…

General Relativity and Quantum Cosmology · Physics 2015-04-06 Mohammad Reza Mehdizadeh , Mahdi Kord Zangeneh , Francisco S. N. Lobo

We construct thin-shell electrically charged wormholes in d-dimensional general relativity with a cosmological constant. The wormholes constructed can have different throat geometries, namely, spherical, planar and hyperbolic. Unlike the…

General Relativity and Quantum Cosmology · Physics 2018-12-05 Gonçalo A. S. Dias , José P. S. Lemos

We investigate the quantum stability of a timelike topological wormhole with a simple geometry $M_2 \times S^2$, supported classically by anisotropic fluid. We compute the one-loop quantum backreaction generated by the vacuum fluctuations…

High Energy Physics - Theory · Physics 2026-03-13 Haris Mehulic , Tomislav Prokopec

Recently, a novel model for a regular black hole was advocated which possesses an asymptotically Minkowski core implemented via an exponential suppression (in the core region) of the Misner-Sharp quasi-local mass. Using this regular black…

General Relativity and Quantum Cosmology · Physics 2020-09-23 Thomas Berry , Francisco S. N. Lobo , Alex Simpson , Matt Visser

In recent years, cosmic observational data have reported that our present universe is undergoing an accelerated expansion, which has been termed as mysterious "dark energy" phenomena, that is, the origin of dark energy has not been…

General Relativity and Quantum Cosmology · Physics 2015-12-11 Deng Wang , Xin-He Meng