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We present a wormhole construction in the framework of the $f(R,T)$ extended gravity theory, with $R$ being the Ricci curvature scalar and $T$ the trace of the energy-momentum tensor, in the case in which the energy-momentum tensor is…

General Relativity and Quantum Cosmology · Physics 2024-10-07 Marcelo Montenegro Lapola

In this present work, we have studied the traversable wormhole geometries in $f(R,T)$ gravity theory, where $R$ denotes the Ricci scalar and $T$ is the trace of the energy-momentum tensor. Firstly, two new shape functions are obtained for…

General Relativity and Quantum Cosmology · Physics 2023-03-01 Bikram Ghosh , Saugata Mitra

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

This paper discusses the feasibility of thin-shell wormholes in spacetimes of embedding class one admitting a one-parameter group of conformal motions. It is shown that the surface energy density $\sigma$ is positive, while the surface…

General Relativity and Quantum Cosmology · Physics 2024-08-13 Peter K. F. Kuhfittig

In this paper we study traversable wormholes in the context of $f(R)$ gravity. Exact solutions of traversable wormholes are found by imposing the nonconstant Ricci scalar. These solutions asymptotically match spherical, flat and hyperbolic…

General Relativity and Quantum Cosmology · Physics 2019-10-23 Hanif Golchin , Mohammad Reza Mehdizadeh

Wormholes are hypothetical shortcuts in spacetime that in General Relativity unavoidably violate all of the pointwise energy conditions. In this paper, we consider several wormhole spacetimes that, as opposed to the standard \emph{designer}…

General Relativity and Quantum Cosmology · Physics 2017-12-19 Cecilia Bejarano , Francisco S. N. Lobo , Gonzalo J. Olmo , Diego Rubiera-Garcia

The objective of this manuscript is to investigate the traversable wormhole solutions in the background of the $f(R, \phi)$ theory of gravity, where $R$ is the Ricci scalar and $\phi$ is the scalar potential respectively. For this reason,…

General Relativity and Quantum Cosmology · Physics 2024-04-05 Adnan Malik , Tayyaba Naz , Abdul Qadeer , M. Farasat Shamir , Z. Yousaf

We investigate possible manifolds characterizing traversable wormholes in the presence of a scalar field minimally coupled to gravity, which has both kinetic and potential energy. The feature of traversability requires the violation of the…

General Relativity and Quantum Cosmology · Physics 2025-10-31 R. Garattini , A. G. Tzikas

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

Models of static wormholes are investigated in the framework of $f(\textit{R}, \textit{T})$ gravity ($\textit{R}$ being the curvature scalar, and $\textit{T}$ the trace of the energy momentum tensor). An attempt to link the energy density…

General Relativity and Quantum Cosmology · Physics 2018-12-31 Emilio Elizalde , Martiros Khurshudyan

In this research work, our primary focus revolves around the examination of a specific category of traversable wormholes known as topologically charged generalized Schwarzschild-Simpson-Visser-type wormhole,…

General Relativity and Quantum Cosmology · Physics 2023-11-29 Faizuddin Ahmed

The condition R=0, where R is the four-dimensional scalar curvature, is used for obtaining a large class (with an arbitrary function of r) of static, spherically symmetric Lorentzian wormhole metrics. The wormholes are globally regular and…

General Relativity and Quantum Cosmology · Physics 2009-11-07 K. A. Bronnikov , Sung-Won Kim

There are some gravitational theories in which the ordinary energy-momentum conservation law is not valid in the curved spacetime. Rastall gravity is one of the known theories in this regard which includes a non-minimal coupling between…

General Relativity and Quantum Cosmology · Physics 2018-04-17 H. Moradpour , N. Sadeghnezhad , S. H. Hendi

An $n$-dimensional Riemannian space is said to be of embedding class $m$ if $n+m$ is the lowest dimension of the flat space in which the given space can be embedded. A spherically symmetric spacetime of class two can be reduced to class one…

General Relativity and Quantum Cosmology · Physics 2021-04-13 Peter K. F. Kuhfittig

This paper explores static wormhole solutions in f(Q,T) theory, where Q is the non-metricity and T is the trace of energy-momentum tensor. We derive the field equations that describe gravitational phenomena in the existence of non-metricity…

General Relativity and Quantum Cosmology · Physics 2024-11-07 M. Zeeshan Gul , M. Sharif , Shajee Shahid , Faisal Javed

We present an analysis of the classic wormhole geometries based on conformal Weyl gravity, rather than standard general relativity. The main characteristics of the resulting traversable wormholes remain the same as in the seminal study by…

General Relativity and Quantum Cosmology · Physics 2016-05-26 Gabriele U. Varieschi , Kellie L. Ault

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

We build five-dimensional spherically symmetric wormholes within the DGP theory. We calculate the energy localized on the shell, and we find that the wormholes could be supported by matter not violating the energy conditions. We also show…

General Relativity and Quantum Cosmology · Physics 2010-09-07 Martín G. Richarte

In this work, we explore the possibility that static and spherically symmetric traversable wormhole geometries are supported by modified teleparallel gravity or f(T) gravity, where T is the torsion scalar. Considering the field equations…

General Relativity and Quantum Cosmology · Physics 2012-02-16 Christian G. Boehmer , Tiberiu Harko , Francisco S. N. Lobo

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