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Related papers: Wormhole geometries in f(R) modified theories of g…

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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

Traversable wormhole solutions are explored in $f(\mathcal{R},\mathbb{T})$ gravity, a curvature--matter extension in which $\mathcal{R}$ is the Ricci scalar and $\mathbb{T}$ denotes the trace of the energy--momentum tensor. To generate…

General Relativity and Quantum Cosmology · Physics 2026-02-02 G. G. L. Nashed , A. Eid

We obtain traversable wormhole and time machine solutions of the field equations of an alternative of gravity with non-minimally curvature-matter coupling. Our solutions exhibit a non-trivial redshift function and allow for matter that…

General Relativity and Quantum Cosmology · Physics 2013-05-30 Orfeu Bertolami , Ricardo Zambujal Ferreira

Alternative gravity is nowadays an extremely important tool to address some persistent observational issues, such as the dark sector of the universe. They can also be applied to stellar astrophysics, leading to outcomes one step ahead of…

General Relativity and Quantum Cosmology · Physics 2019-08-15 P. H. R. S. Moraes , P. K. Sahoo

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

In this paper, we study the energy conditions of charged traversable wormholes in the framework of $f(R, \mathscr{L}_m)$ modified gravity. In the first case, we derive the shape functions (SFs) for two different choices of the charge…

General Relativity and Quantum Cosmology · Physics 2026-05-18 Sagar V. Soni , A. C. Khunt , Farook Rahaman , A. H. Hasmani

We present a traversable wormhole solution using the traceless $f(R,T)$ theory of gravity. In the $f(R,T)$ gravity, the Ricci scalar $R$ in the Einstein-Hilbert action is replaced by a function of $R$ and trace of the energy momentum tensor…

General Relativity and Quantum Cosmology · Physics 2021-09-02 Parbati Sahoo , P. H. R. S. Moraes , Marcelo M. Lapola , P. K. Sahoo

We show that the violation of the null energy condition by matter, required by traversable wormholes, can be removed in spacetimes with torsion. In addition, we show that this violation can also be removed in the conformal frame obtained by…

General Relativity and Quantum Cosmology · Physics 2018-12-14 Fayçal Hammad , Étienne Massé , Patrick Labelle

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 the present article we propose a new hybrid shape function for wormhole (WH)s in the modified $f(R,T)$ gravity. The proposed shape function satisfied the conditions of WH geometry. Geometrical behavior of WH solutions are discussed in…

General Relativity and Quantum Cosmology · Physics 2020-05-22 Parbati Sahoo , Sanjay Mandal , P. K. Sahoo

Here, we propose a new exponential shape function in wormhole geometry within modified gravity. The energy conditions and equation of state parameter are obtained. The radial and tangential null energy conditions are validated, as well as…

We propose, as a novelty in the literature, the modelling of wormholes within the particular case of the $f(R,T)$ gravity, namely $f(R,T)=R+\alpha R^{2}+\lambda T$, with $R$ and $T$ being the Ricci scalar and trace of the energy-momentum…

General Relativity and Quantum Cosmology · Physics 2018-01-23 P. K. Sahoo , P. H. R. S. Moraes , Parbati Sahoo

This paper investigates static spherically symmetric traversable wormhole solutions in $f(\mathcal{G},T)$ gravity ($\mathcal{G}$ and $T$ represent the Gauss-Bonnet invariant and trace of the energy-momentum tensor, respectively). We…

General Relativity and Quantum Cosmology · Physics 2018-01-10 M. Sharif , Ayesha Ikram

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

The static spherically symmetric traversable wormholes are analysed in the Einstein- Cartan theory of gravitation. In particular, we computed the torsion tensor for matter fields with different spin S = 0; 1/2; 1; 3/2. Interestingly, only…

General Relativity and Quantum Cosmology · Physics 2018-01-12 Emmanuele Battista , Elisabetta Di Grezia , Mattia Manfredonia , Gennaro Miele

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 paper, we examine the existence of traversable wormhole solutions within the Chern-Simons modified gravity. We find a non-trivial solution in the theory with dynamical Chern-Simons coefficient in the absence of matter sources. This…

General Relativity and Quantum Cosmology · Physics 2018-01-10 J. R. Nascimento , A. Yu. Petrov , P. J. Porfirio

In this paper, we use the embedding class-I technique to examine the effect of charge on traversable wormhole geometry in the context of $f(\mathcal{G})$ theory, where $\mathcal{G}$ is the Gauss-Bonnet term. For this purpose, we consider…

General Relativity and Quantum Cosmology · Physics 2024-03-04 M. Zeeshan Gul , M. Sharif

Morris and Thorne \cite{morris1} proposed traversable wormholes, hypothetical connecting tools, using the concept of Einstein's general theory of relativity. In this paper, the modification of general relativity (in particular $f(R,T)$…

General Relativity and Quantum Cosmology · Physics 2020-05-05 Nisha Godani , Gauranga C. Samanta

Wormholes are speculative structures linking disparate space-time points. Their geometry can be obtained by solving Einstein equations with tolerating the violation of null energy conditions. Recently, many researchers have studied…

General Relativity and Quantum Cosmology · Physics 2022-03-10 J. Sadeghi , B. Pourhassan , S. Noori Gashti , S. Upadhyay
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