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In this manuscript, we explore the existence of wormhole solutions exhibiting spherical symmetry in a modified gravity namely $f(R,T)$ theory by involving some aspects of non-commutative geometry. For this purpose, we consider the…

General Relativity and Quantum Cosmology · Physics 2020-04-02 M. Zubair , Saira Waheed , G. Mustafa , Hamood Ur Rehman

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

In this paper, we evaluate traversable wormhole solutions through Karmarkar condition in $f(R,T)$ theory, where $T$ is the trace of the energy-momentum tensor and $R$ represents the Ricci scalar. We develop a wormhole shape function for the…

General Relativity and Quantum Cosmology · Physics 2023-03-06 M. Sharif , Arooj Fatima

In this paper, we discuss spherically symmetric wormhole solutions in $f(R,T)$ modified theory of gravity by introducing well-known non-commutative geometry in terms of Gaussian and Lorentizian distributions of string theory. For some…

General Physics · Physics 2018-11-14 M. Zubair , G. Mustafa , Saira Waheed , G. Abbas

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

We show that, in contrast to general relativity, in Eddington-inspired Born-Infeld gravity (EiBI), a violation of the null convergence condition does not necessarily lead to a violation of the null energy condition, by establishing a…

General Relativity and Quantum Cosmology · Physics 2018-09-18 Rajibul Shaikh

Among the several modified/extended gravity paradigms, the concept of antisymmetric connections leading to space-time torsion can be traced back to Cartan. More recently, developments in string theory have suggested the existence of a…

General Relativity and Quantum Cosmology · Physics 2023-06-01 Parangam Goswami , Anshuman Baruah , Atri Deshamukhya

We provide a new matter source that supplies fuel to construct wormhole spacetime. The exact wormhole solutions are found in the model having, besides real matter, an anisotropic dark energy. We have shown that the exotic matters that are…

General Physics · Physics 2013-03-14 Farook Rahaman , Saibal Ray , Safiqul Islam

The current study examines the geometry of static wormholes with anisotropic matter distribution in context of modified $f(\mathcal{G})$ gravity. We consider the well known Noether and conformal symmetries, which help in investigating…

General Relativity and Quantum Cosmology · Physics 2023-04-14 Tayyaba Naz , G. Mustafa , M. Farasat Shamir

In this study, we reach the equations of motion of Morris-Thorne wormhole geometry by means of the Einstein Field Equations and Klein-Gordon Equation of Scalar-Tensor theory by direct calculation. We discuss the anisotropic matter energy…

General Relativity and Quantum Cosmology · Physics 2018-07-19 Onur Genç

We discuss a proposal on how gravitational collapse of a NEC (Null Energy Condition) violating spherically symmetric fluid distribution can avoid the formation of a zero proper volume singularity and eventually lead to a Lorentzian wormhole…

General Relativity and Quantum Cosmology · Physics 2021-08-11 Soumya Chakrabarti , Sayan Kar

We consider the possibility that wormhole geometries are sustained by their own quantum fluctuations, in the context of noncommutative geometry and Gravity's Rainbow models. More specifically, the energy density of the graviton one-loop…

General Relativity and Quantum Cosmology · Physics 2013-01-03 Remo Garattini , Francisco S. N. Lobo

In quadratic gravity, the junction conditions are six and permit the appearance of double layer thin shells. Double layers arise typically in theories with dipoles, i.e., two opposite charges, such as electromagnetic theories, and appear…

General Relativity and Quantum Cosmology · Physics 2023-05-12 Joao Luís Rosa , Rui André , José P. S. Lemos

A dynamical theory of traversable wormholes is detailed in spherical symmetry. Generically a wormhole consists of a tunnel of trapped surfaces between two mouths, defined as temporal outer trapping horizons with opposite senses, in mutual…

General Relativity and Quantum Cosmology · Physics 2009-06-30 Sean A. Hayward

I prove that general relativity admits no asymptotically well-behaved static spherically symmetric traversable wormholes supported by classical scalar fields and nonexotic matter. The theorem holds for all values of the scalar field…

General Relativity and Quantum Cosmology · Physics 2015-06-11 Luke M. Butcher

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

We propose wormholes solutions by assuming space dependent equation of state parameter. Our models show that the existence of wormholes is supported by arbitrary small quantities of averaged null energy condition (ANEC) violating phantom…

General Relativity and Quantum Cosmology · Physics 2009-04-24 F. Rahaman , M. Kalam , S. Chakraborty

In this work we show the existence of traversable wormhole and time-machine solutions in a modified theory of gravity where matter and curvature are nonminimally coupled. Those solutions present a nontrivial redshift function and exist even…

High Energy Physics - Theory · Physics 2013-10-24 Orfeu Bertolami , Ricardo Zambujal Ferreira

In this study, both the evolution of wormholes (by examining both the energy conditions and using the TOV equations) and the effects of the Karmarkar condition on the solutions obtained under certain specific cases were examined in the…

General Relativity and Quantum Cosmology · Physics 2025-06-04 Murat Metehan Turkoglu

This research work provides an exhaustive investigation of the viability of different coupled wormhole (WH) geometries with the relativistic matter configurations in the $f(R,G,T)$ extended gravity framework. We consider a specific model in…

General Relativity and Quantum Cosmology · Physics 2025-04-01 M. Ilyas , A. R. Athar , Fawad Khan , Nasreen Ghafoor , Haifa I. Alrebdi , Kottakkaran Sooppy Nisar , Abdel-Haleem Abdel-Aty