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Related papers: Nonexistence theorems for traversable wormholes

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The ghost-free bi-metric gravity theory is a viable theory of gravity that explores the interaction between a massless and a massive graviton and can be described in terms of two dynamical metrics. In this paper, we present an exact static,…

General Relativity and Quantum Cosmology · Physics 2023-11-14 Mostafizur Rahman , Anjan A Sen , Sunil Singh Bohra

We provide a prescription of real feasible sources that supply fuel to construct a traversable wormhole. A class of exact solutions for Einstein-Maxwell field equations describing wormhole with an anisotropic matter distribution has been…

General Relativity and Quantum Cosmology · Physics 2009-02-18 F. Rahaman , M. Kalam , K. A. Rahman

Wormholes with Ellis geometry have been successfully constructed using tachyon matter \cite{Das}. However, for such a wormhole, it is obtained that the redshift function is necessarily a constant, and also the wormhole is plagued with an…

General Relativity and Quantum Cosmology · Physics 2022-05-13 Rikpratik Sengupta , Shounak Ghosh , Mehedi Kalam

Noncommutative geometry, an offshoot of string theory, replaces point-like particles by smeared objects. These local effects have led to wormhole solutions in a semiclassical setting, but it has also been claimed that the noncommutative…

General Relativity and Quantum Cosmology · Physics 2024-12-24 Peter K. F. Kuhfittig

It is generally agreed that the acceleration of the Universe can best be explained by the presence of dark or phantom energy. The equation of state of the latter shows that the null energy condition is violated. Such a violation is the…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Mubasher Jamil , Peter K. F. Kuhfittig , Farook Rahaman , Sk. A Rakib

We study Lorentzian wormholes in the ghost-free bigravity theory described by two metrics, g and f. Wormholes can exist if only the null energy condition is violated, which happens naturally in the bigravity theory since the graviton…

High Energy Physics - Theory · Physics 2015-06-17 Sergey V. Sushkov , Mikhail S. Volkov

In this paper, the gravitational deflection of relativistic massive particles up to the second post-Minkowskian order by static and spherically symmetric wormholes is investigated in the weak-field limit. These wormholes include the…

General Relativity and Quantum Cosmology · Physics 2020-02-05 Zonghai Li , Guansheng He , Tao Zhou

The purpose of this paper is to obtain exact solutions of the Einstein field equations describing traversable wormholes supported by phantom energy. Their relationship to exact solutions in the literature is also discussed, as well as the…

General Relativity and Quantum Cosmology · Physics 2015-04-06 Peter K. F. Kuhfittig

In this work we demonstrate that wormholes can in principle be naturally created during the cosmological bounce without the need for the exotic matter or any kind of additional modifications of the gravitational sector, apart from the one…

General Relativity and Quantum Cosmology · Physics 2025-02-07 Petar Pavlović , Marko Sossich

It is well-known that traversable wormhole solutions to the Einstein equations require the existence of an exotic matter source violating the null energy condition. An apparent exception is the overcharged Kerr-Newman-NUT solution of the…

General Relativity and Quantum Cosmology · Physics 2023-01-24 Gérard Clément , Dmitri Gal'tsov

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

We study the properties of evolving wormholes able to exist in a closed Friedmann dust-filled universe and described by a particular branch of the well-known Lema{\i}tre-Tolman-Bondi solution to the Einstein equations and its generalization…

General Relativity and Quantum Cosmology · Physics 2023-11-14 Kirill A. Bronnikov , Pavel E. Kashargin , Sergey V. Sushkov

We explore the existence of Lorentzian wormholes in the context of an effective on-brane, scalar-tensor theory of gravity. In such theories, the timelike convergence condition, which is always violated for wormholes, has contributions, via…

General Relativity and Quantum Cosmology · Physics 2015-10-28 Sayan Kar , Sayantani Lahiri , Soumitra SenGupta

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

In this paper, we consider third order Lovelock gravity with a cosmological constant term in an n-dimensional spacetime $\mathcal{M}^{4}\times \mathcal{K}^{n-4}$, where $\mathcal{K}^{n-4} $ is a constant curvature space. We decompose the…

General Relativity and Quantum Cosmology · Physics 2015-12-23 Mahdi Kord Zangeneh , Francisco S. N. Lobo , Mohammad Hossein Dehghani

In this work, the study of traversable wormholes in $f(R)$ gravity with the function $f(R)=R+\alpha R^n$, where $\alpha$ and $n$ are arbitrary constants, is taken into account. The shape function $b(r)=\frac{r}{\exp(r-r_0)}$, proposed by…

General Relativity and Quantum Cosmology · Physics 2020-01-29 Nisha Godani , Gauranga C. Samanta

In this paper we study the possibility of sustaining an evolving wormhole via exotic matter made out of phantom energy. We show that this exotic source can support the existence of evolving wormhole spacetimes. Explicitly, a family of…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Mauricio Cataldo , Pedro Labrana , Sergio del Campo , Juan Crisostomo , Patricio Salgado

We consider $f(R, T)$ theory of gravity, in which the gravitational Lagrangian is given by an arbitrary function of the Ricci scalar and the trace of the energy-momentum tensor, to study static spherically symmetric wormhole geometries…

General Relativity and Quantum Cosmology · Physics 2021-08-03 Ayan Banerjee , M. K. Jasim , Sushant G. Ghosh

A non-singular Emergent Universe (EU) scenario within the realm of standard Relativistic physics requires a generalization of the Equation of State (EoS) connecting the pressure and energy density. This generalized EoS is capable of…

General Relativity and Quantum Cosmology · Physics 2023-04-10 Rikpratik Sengupta , Shounak Ghosh , B C Paul , Mehedi Kalam

Traversable wormholes have traditionally been viewed as intrinsically topological entities in some multiply connected spacetime. Here, we show that topology is too limited a tool to accurately characterize a generic traversable wormhole: in…

General Relativity and Quantum Cosmology · Physics 2011-09-30 David Hochberg , Matt Visser
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