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Related papers: Modified-gravity wormholes without exotic matter

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A fundamental property in wormhole physics is the flaring-out condition of the throat, which through the Einstein field equation entails the violation of the null energy condition. In the context of modified theories of gravity, it has also…

General Relativity and Quantum Cosmology · Physics 2012-11-07 Francisco S. N. Lobo

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

A fundamental property of Morris-Thorne wormholes is the so-called flare-out condition that automatically results in a violation of the null energy condition (NEC) in classical general relativity. By contrast, in $f(R)$ modified gravity,…

General Relativity and Quantum Cosmology · Physics 2020-08-20 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

In the present article, models of traversable wormholes within the $f(R, T)$ modified gravity theory are investigated. We have presented some wormhole models, developed from various hypothesis for the substance of their matter, i.e. various…

General Physics · Physics 2021-08-03 Ambuj Kumar Mishra , Umesh Kumar Sharma , Vipin Chandra Dubey , Anirudh Pradhan

We establish a general no--go theorem demonstrating that all traversable wormhole configurations in Unimodular Gravity necessarily require exotic matter. The proof relies solely on the geometric flaring-out condition, $b'(r_0) \leq 1$,…

General Relativity and Quantum Cosmology · Physics 2026-04-07 Mauricio Cataldo , Norman Cruz , Patricio Salgado

We study wormhole solutions in the framework of f (R,T) gravity where R is the scalar curvature, and T is the trace of the stress-energy tensor of the matter. We have obtained the shape function of the wormhole by specifying an equation of…

General Relativity and Quantum Cosmology · Physics 2014-01-30 Tahereh Azizi

We study the existence and properties of wormhole throats in modified $f(R)$ gravity theory. Specifically, we concentrate on the cases where the lapse is not necessarily constant, and hence are not limited to the zero tidal force scenarios.…

General Relativity and Quantum Cosmology · Physics 2015-03-19 Andrew DeBenedictis , Dubravko Horvat

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

We consider the possibility of multiply-connected spacetimes, ranging from the Flamm-Einstein-Rosen bridge, geons, and the modern renaissance of traversable wormholes. A fundamental property in wormhole physics is the flaring-out condition…

General Relativity and Quantum Cosmology · Physics 2016-06-14 Francisco S. N. Lobo

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

Holding a Morris-Thorne wormhole open requires a violation of the null energy condition, calling for the need for so-called exotic matter near the throat. Many researchers consider exotic matter to be completely unphysical in classical…

General Relativity and Quantum Cosmology · Physics 2024-03-01 Peter K. F. Kuhfittig

This paper discusses the possible existence of traversable wormholes in f(R) modified gravity while assuming a noncommutative-geometry background, as well as zero tidal forces. The first part of the paper aims for an overview via several…

General Relativity and Quantum Cosmology · Physics 2020-07-28 Peter K. F. Kuhfittig

We review recent work on wormhole geometries in the context of modified theories of gravity, in particular, in f(R) gravity and with a nonminimal curvature-matter coupling, and in the recently proposed hybrid metric-Palatini theory. In…

General Relativity and Quantum Cosmology · Physics 2013-10-18 Francisco S. N. Lobo

We study static traversable wormholes obtained by Morris and Thorne in general relativity (GR) in the framework of a modified theory of gravity. The modified gravitational action $f(R,T)$ is a function of the Ricci scalar ($R$) and of the…

General Relativity and Quantum Cosmology · Physics 2021-08-25 A Chanda , S Dey , B C Paul

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

We consider $f(R, T)$ theory of gravity, in which the gravitational Lagrangian is given by an arbitrary function of the Ricci scalar and the trace of the energy-momentum tensor, to study static spherically symmetric wormhole geometries…

General Relativity and Quantum Cosmology · Physics 2021-08-03 Ayan Banerjee , M. K. Jasim , Sushant G. Ghosh

Spacetime wormholes are evidently an essential component of the construction of a time machine. Within the context of general relativity, such objects require, for their formation, exotic matter -- matter that violates at least one of the…

General Relativity and Quantum Cosmology · Physics 2024-06-13 Mengqi Lu , Jiayue Yang , Robert B. Mann

For a generic $f(R)$ which admits a polynomial expansion of at least third order (i.e. $\frac{d^{3}f}{dR^{3}}\neq 0$) we find the near-throat wormhole solution. Necessary conditions for the existence of wormholes in such $f(R)$ theories are…

General Relativity and Quantum Cosmology · Physics 2016-11-15 S. Habib Mazharimousavi , M. Halilsoy
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