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Related papers: Noncommutative-geometry wormholes based on the Cas…

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In this paper we show that wormholes in (2+1) dimensions (3-D) cannot be sourced solely by both Casimir energy and tension, differently from what happens in a 4-D scenario, in which case it has been shown recently, by the direct computation…

General Relativity and Quantum Cosmology · Physics 2021-11-03 G. Alencar , V. B. Bezerra , C. R. Muniz

We construct and analyse wormhole solutions in quantised space-time. The field equations are constructed from the deformed wormhole metric in the proper reference frame using tetrads. The spatial geometry of the wormhole is analysed in the…

General Relativity and Quantum Cosmology · Physics 2025-01-28 Harsha Sreekumar , E. Harikumar

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

In this letter, we investigate the changes in the quantum vacuum energy density of a massless scalar field inside a Casimir cavity that orbits a wormhole, by considering the cosmological model with an isotropic form of the Morris-Thorne…

General Relativity and Quantum Cosmology · Physics 2024-09-05 A. C. L. Santos , C. R. Muniz , L. T. Oliveira

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

The Einstein-Cartan (EC) theory of gravity provides a natural extension of general relativity by incorporating spacetime torsion to account for the intrinsic spin of matter. In this work, we investigate Yukawa-Casimir traversable wormholes…

General Relativity and Quantum Cosmology · Physics 2025-10-17 Nayan Sarkar , Susmita Sarkar , Abdelmalek Bouzenada

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

In this paper we seek a relationship between the assumption of conformal symmetry and the exotic matter needed to hold a wormhole open. By starting with a Morris-Thorne wormhole having a constant energy density, it is shown that the…

General Relativity and Quantum Cosmology · Physics 2024-02-20 Peter K. F. Kuhfittig

We show that the presence of a nonminimal interaction between dark matter and dark energy may lead to a violation of the null energy condition and to the formation of a configuration with nontrivial topology (a wormhole). In this it is…

General Relativity and Quantum Cosmology · Physics 2014-03-11 Vladimir Folomeev , Vladimir Dzhunushaliev

In recent years there has been a growing interest in the field of wormhole physics in the presence of the Casimir effect. As this effect provides negative energy density, it can be utilized as an ideal candidate for the exotic matter…

General Relativity and Quantum Cosmology · Physics 2024-06-18 Amir Hadi Ziaie , Mohammad Reza Mehdizadeh

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

The theoretical construction of a traversable wormhole proposed by Morris and Thorne maintains complete control over the geometry by assigning both the shape and redshift functions, thereby leaving open the determination of the…

General Relativity and Quantum Cosmology · Physics 2020-07-27 Peter K. F. Kuhfittig

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

We present a traversable-wormhole solution of the gravitational field equation of General Relativity without need of exotic matter (exotic matter can, for example, have negative energy density and vanishing isotropic pressure). Instead of…

General Relativity and Quantum Cosmology · Physics 2023-06-16 F. R. Klinkhamer

Traversable wormholes in General Relativity (GR) require exotic matter sources that violate the null energy condition (NEC), and such behavior may be avoided in modified gravity. Moreover, the concept of non-commutative geometry as a…

General Relativity and Quantum Cosmology · Physics 2022-10-18 Anshuman Baruah , Parangam Goswami , Atri Deshamukhya

Noncommutative geometry, as conceptualized by Nicolini, Smailagic, and Spallucci, may be viewed as a slight modification of Einstein's theory. The same can be said for $f(R)$ modified gravity for an appropriate choice of the function…

General Relativity and Quantum Cosmology · Physics 2021-01-05 Peter K. F. Kuhfittig

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

In this paper we discuss the Casimir effect in a small cavity, freely falling from spatial infinity in spacetime geometry outside of a Schwarzschild black hole. Our main goal is to search for possible changes in the vacuum energy, as well…

General Relativity and Quantum Cosmology · Physics 2019-11-20 Francesco Sorge , Justin H. Wilson

The existing solutions to the Einstein equations describing rotating cylindrical wormholes are not asymptotically flat and therefore cannot describe wormhole entrances as local objects in our Universe. To overcome this difficulty, flat…

General Relativity and Quantum Cosmology · Physics 2016-03-30 K. A. Bronnikov

Traversable wormholes necessarily require violations of the averaged null energy condition; this being the definition of ``exotic matter''. However, the theorems which guarantee the energy condition violation are remarkably silent when it…

General Relativity and Quantum Cosmology · Physics 2011-07-18 Matt Visser , Sayan Kar , Naresh Dadhich