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Related papers: Evolving Wormholes in a Cosmological Background

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A new framework is proposed for general dynamic wormholes, unifying them with black holes. Both are generically defined locally by outer trapping horizons, temporal for wormholes and spatial or null for black and white holes. Thus wormhole…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Sean A. Hayward

We explore the properties of traversable wormhole spacetimes within the framework of energy-momentum squared gravity, also known as $f(R,T^2)$ gravity, where $R$ represents the Ricci scalar, $T_{ab}$ is the energy-momentum tensor, and $T^2…

General Relativity and Quantum Cosmology · Physics 2025-02-27 Nailya Ganiyeva , João Luís Rosa , Francisco S. N. Lobo

The discovery that the Universe is undergoing an accelerated expansion has suggested the existence of an evolving equation of state. This paper discusses various wormhole solutions in a spherically symmetric spacetime with an equation of…

General Relativity and Quantum Cosmology · Physics 2011-03-15 Peter K. F. Kuhfittig

Some problems of the space-time causal structure are discussed using models with traversable wormholes. For this purpose the conditions of traversable wormhole matching with the exterior space-time are considered in detail and a mixed…

General Relativity and Quantum Cosmology · Physics 2011-04-15 M. Yu. Konstantinov

In the present article, models of traversable wormholes within the $f(R, T)$ modified gravity theory are investigated. We have presented some wormhole models, developed from various hypothesis for the substance of their matter, i.e. various…

General Physics · Physics 2021-08-03 Ambuj Kumar Mishra , Umesh Kumar Sharma , Vipin Chandra Dubey , Anirudh Pradhan

Traversable wormholes in General Relativity (GR) require exotic matter sources that violate the null energy condition (NEC), and such behavior may be avoided in modified gravity. Moreover, the concept of non-commutative geometry as a…

General Relativity and Quantum Cosmology · Physics 2022-10-18 Anshuman Baruah , Parangam Goswami , Atri Deshamukhya

A possible cause of the late-time cosmic acceleration is an exotic fluid with an equation of state lying within the phantom regime, i.e., $w=p/\rho <-1$. The latter violates the null energy condition, which is a fundamental ingredient in…

General Relativity and Quantum Cosmology · Physics 2013-04-12 Francisco S. N. Lobo , Foad Parsaei , Nematollah Riazi

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

A fundamental ingredient in wormhole physics is the presence of exotic matter, which involves the violation of the null energy condition. Although a plethora of wormhole solutions have been explored in the literature, it is useful to find…

General Relativity and Quantum Cosmology · Physics 2012-07-19 Francisco S. N. Lobo

Wormhole solutions to the equations of general relativity have some spectacular local and global properties. As these unusual features are not explicitly forbidden by known physics, wormholes are considered in various astrophysical and…

General Relativity and Quantum Cosmology · Physics 2022-08-31 Daniel R. Terno

In the present work we investigate evolving wormhole configurations described by a constant redshift function in Einstein-Cartan theory ({{\sf ECT}}). The matter content consists of a Weyssenhoff fluid along with an anisotropic matter which…

General Relativity and Quantum Cosmology · Physics 2017-12-19 Mohammad Reza Mehdizadeh , Amir Hadi Ziaie

While wormholes may be just as good a prediction of Einstein's theory as black holes, they are subject to severe restrictions from quantum field theory. In particular, a wormhole can only be held open by violating the null energy condition,…

General Relativity and Quantum Cosmology · Physics 2025-03-31 Peter K. F. Kuhfittig

This paper discusses the possible existence of traversable wormholes in f(R) modified gravity while assuming a noncommutative-geometry background, as well as zero tidal forces. The first part of the paper aims for an overview via several…

General Relativity and Quantum Cosmology · Physics 2020-07-28 Peter K. F. Kuhfittig

The current interests in the universe motivate us to go beyond Einstein's General theory of relativity. One of the interesting proposals comes from a new class of teleparallel gravity named symmetric teleparallel gravity, i.e., $f(Q)$…

General Relativity and Quantum Cosmology · Physics 2021-06-09 Zinnat Hassan , Sanjay Mandal , P. K. Sahoo

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

Various spacetime candidates for traversable wormholes, regular black holes, and `black-bounces' are presented and thoroughly explored in the context of the gravitational theory of general relativity. All candidate spacetimes belong to the…

General Relativity and Quantum Cosmology · Physics 2021-04-30 Alex Simpson

In this work, we construct time-dependent wormhole solutions in the context of $f(R)$ theory of gravity. The background matter is considered to be traceless. By considering specific shape function and power-law expansion exact solutions for…

General Physics · Physics 2014-09-09 H. Saiedi , B. Nasr Esfahani

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

This study aims to investigate the physical properties of wormhole geometry within the context of $f(T,\mathcal{T})$ gravity, which serves as a teleparallel formulation of general relativity. We study a linear model,…

General Relativity and Quantum Cosmology · Physics 2025-04-15 Foad Parsaei , Sara Rastgoo

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