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Related papers: Necessary conditions for having wormholes in f(R) …

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In the present paper, we investigate wormholes in 4D-Einstein-Gauss-Bonnet gravity without the requirement of exotic matters. We have taken the radial dependent red-shift function $\phi=\ln \left( {\frac {r_{{0}}}{r}}+1 \right)$ and shape…

General Relativity and Quantum Cosmology · Physics 2022-11-23 Ambuj Kumar Mishra , Shweta , Umesh Kumar Sharma

In the framework of the theory of general relativity, in order to obtain stable traversable wormholes, matter needs to violate the null energy condition. It is well known that the violation of the energy condition (EC) of matter leads to…

General Relativity and Quantum Cosmology · Physics 2024-03-22 Jianbo Lu , Shining Yang , Yan Liu , Yuying Zhang , Yu Liu

We build spherically symmetric wormholes within the DGP theory. We calculate the energy localized on the shell, and we find that for certain values of the parameters wormholes could be supported by matter not violating the energy…

General Relativity and Quantum Cosmology · Physics 2015-03-17 Martín G. Richarte

We explore the possibility of dynamic wormhole geometries, within the context of nonlinear electrodynamics. The Einstein field equation imposes a contracting wormhole solution and the obedience of the weak energy condition. Furthermore, in…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Aaron V. B. Arellano , Francisco S. N. Lobo

In this article, we have discussed Morris and Thorne (MT) wormhole solutions in a modified theory of gravity that admits conformal motion. Here we explore the wormhole solutions in $f(R,\,T)$ gravity, which is a function of the Ricci scalar…

General Relativity and Quantum Cosmology · Physics 2022-05-04 Piyali Bhar , Pramit Rej , P. K. Sahoo

We present a family of charged, traversable wormhole solutions in the presence of a cosmological constant. In de Sitter spacetime, two types of wormhole throats can exist--referred to as typical and cosmological throat--located at small and…

General Relativity and Quantum Cosmology · Physics 2026-01-13 Hyeong-Chan Kim , Wonwoo Lee

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

We formulate the traversability of wormhole throats as a local and covariant null defocusing condition derived from the Raychaudhuri equation. Since unimodular gravity preserves the local geometric structure of spacetime, the null focusing…

General Relativity and Quantum Cosmology · Physics 2026-02-03 Erick Pastén , Marco Bosquez , Norman Cruz

This thesis explores traversable wormhole (WH) solutions within symmetric teleparallel gravity and its extensions, including $f(Q)$ and $f(Q, T)$ gravity. Chapter I reviews WH geometry and properties, general relativity, and modified…

General Relativity and Quantum Cosmology · Physics 2025-05-09 Moreshwar Tayde

Following the recent theory of Lovelock-Brans-Dicke gravity, we continue to investigate the conditions to support traversable wormholes by the gravitational effects of spacetime parity and topology, which arise from the nonminimal couplings…

General Relativity and Quantum Cosmology · Physics 2016-01-08 David Wenjie Tian

Within 2+1-dimensional cosmological new massive gravity, we consider thin-shell and thin-shell wormhole construction. For this, we introduce first, the junction conditions apt for the fourth order terms in the action of the theory. Then, by…

General Relativity and Quantum Cosmology · Physics 2019-06-04 S. Danial Forghani , S. Habib Mazharimousavi , M. Halilsoy

This paper discusses the possibility of traversable wormholes in the galactic region supported by dark matter (DM) models and global monopole charge in the context of $f(Q)$ gravity. To understand the features of the wormholes, we…

General Relativity and Quantum Cosmology · Physics 2024-09-05 Moreshwar Tayde , P. K. Sahoo

A basic constraint to be satisfied by Brans class I solution for being a traversible wormhole is derived. It is argued that the solution could be a wormhole analogue of the Horowitz-Ross naked black hole. It is further demonstrated that the…

General Relativity and Quantum Cosmology · Physics 2010-03-25 Amrita Bhattacharya , Ilnur Nigmatzyanov , Ramil Izmailov , Kamal K. Nandi

A Morris-Thorne wormhole can only be sustained by violating the null energy condition, thereby requiring the existence of "exotic matter," a requirement that many researchers consider unphysical. Using a mostly qualitative approach, it is…

General Relativity and Quantum Cosmology · Physics 2024-04-09 Peter K. F. Kuhfittig

While wormholes are just as good a prediction of Einstein's theory as black holes, they are subject to severe restrictions from quantum field theory. To allow for the possibility of interstellar travel, a macroscopic wormhole would need to…

General Relativity and Quantum Cosmology · Physics 2024-09-25 Peter K. F. Kuhfittig

Exact solutions of traversable wormholes are found under the assumption of spherical symmetry and the existence of a {\it non-static} conformal symmetry, which presents a more systematic approach in searching for exact wormhole solutions.…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Christian G. Boehmer , Tiberiu Harko , Francisco S. N. Lobo

A class of $f(R, T)$ theories extends the Einstein-Hilbert action by incorporating a general function of $R$ and $T$, the Ricci scalar and the trace of the ordinary energy-momentum tensor $T_{\mu\nu}$, respectively, thereby introducing a…

General Relativity and Quantum Cosmology · Physics 2025-07-30 Yaghoub Heydarzade , Maryam Ranjbar

Traversable wormholes, tunnel like structures introduced by Morris \& Thorne \cite{morris1}, have a significant role in connection of two different space-times or two different parts of the same space-time. The characteristics of these…

General Relativity and Quantum Cosmology · Physics 2019-02-20 Nisha Godani , Gauranga C. Samanta

In this thesis, we investigate traversable wormhole spacetimes within the context of a covariant generalization of Einstein's General Relativity, namely the energy-momentum squared gravity, denoted as $f\left(R,T_{ab}T^{ab}\right)$. Here,…

General Relativity and Quantum Cosmology · Physics 2024-12-13 Nailya Ganiyeva

We consider wormhole geometries subject to a gravitational action consisting of non-linear powers of the Ricci scalar. Specifically, wormhole throats are studied in the case where Einstein gravity is supplemented with a Ricci-squared and…

General Relativity and Quantum Cosmology · Physics 2007-05-23 N. Furey , A. DeBenedictis