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Related papers: Wormholes in a viscous universe

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This study presents new spherically symmetric and dynamical wormhole solutions supported by ordinary matter modeled as an anisotropic fluid, exhibiting a traversable nature. To achieve this goal, we adopt different approaches to obtain both…

General Relativity and Quantum Cosmology · Physics 2025-04-29 M. Zubair , Hina Azmat , Quratulien Muneer , Saira Waheed , M. B. Cruz

This work presents new three-dimensional traversable wormhole solutions sourced by the Casimir density and pressures related to the quantum vacuum fluctuations in Yang-Mills (Y-M) theory. We begin by analyzing the noninteracting Y-M Casimir…

General Relativity and Quantum Cosmology · Physics 2023-09-20 Alana C. L. Santos , Célio R. Muniz , Roberto V. Maluf

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

The present work deals with a spherically symmetric space-time which is asymptotically (at spatial infinity) FRW space-time and represents wormhole configuration: The matter component is divided into two parts--(a) dissipative but…

General Relativity and Quantum Cosmology · Physics 2015-01-27 Supriya Pan , Subenoy Chakraborty

Bulk viscosity, which characterizes the irreversible dissipative resistance of a fluid to volume changes, has been proposed as a potential mechanism for explaining both early- and late-time accelerated expansion of the Universe. In this…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-18 P. P. Avelino , A. R. Gomes , D. A. Tamayo

Motivated by recent proposals of possible wormhole existence in galactic halos, we analyse the cosmological evolution of wormhole solutions in modified $f(R)$ gravity. We construct a dynamical wormhole that asymptotically approaches FLRW…

General Relativity and Quantum Cosmology · Physics 2016-08-24 Sebastian Bahamonde , Mubasher Jamil , Petar Pavlovic , Marko Sossich

The first junction conditions of spherically symmetric bubbles are solved for some cases, and whereby analytic models to the Einstein field equations are constructed. The effects of bubbles on the spacetime structure are studied and it is…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Anzhong Wang , Patricio S. Letelier

In this study, we explore the new wormhole solutions in the framework of new modified $f(R,L_m)$ gravity. To obtain a characteristic wormhole solution, we use anisotropic matter distribution and a specific form of energy density. As second…

General Relativity and Quantum Cosmology · Physics 2023-05-12 N. S. Kavya , V. Venkatesha , G. Mustafa , P. K. Sahoo , S. V. Divya Rashmi

In this paper, we study anisotropic Bianchi-V universe with magnetic field and bulk viscous fluid in string cosmology. Exact solutions of the field equations are obtained by using the equation of state for a cloud of strings, and a…

General Relativity and Quantum Cosmology · Physics 2012-11-28 C. P. Singh , Vijay Singh

We study the stability of static, spherically symmetric, traversable wormholes existing due to conformal continuations in a class of scalar-tensor theories with zero scalar field potential (so that Fisher's well-known scalar-vacuum solution…

General Relativity and Quantum Cosmology · Physics 2016-08-31 K. A. Bronnikov , S. V. Grinyok

Spherically symmetric thin-shell wormholes in the presence of a cosmological constant are constructed applying the cut-and-paste technique implemented by Visser. Using the Darmois-Israel formalism the surface stresses, which are…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Francisco S. N. Lobo , Paulo Crawford

It has been recently claimed that dark matter could be in the form of a Bose-Einstein condensate (BEC) in order to explain the dynamics at large distances from the galactic center [Boehmer, Harko, JCAP {\bf 0706}, 025 (2007)]. In this paper…

General Relativity and Quantum Cosmology · Physics 2019-08-27 Kimet Jusufi , Mubasher Jamil , Muhammad Rizwan

We consider the influence of the perturbative bulk viscosity on the evolution of the Hubble parameter in the QCD era of the early Universe. For the geometry of the Universe we assume the homogeneous and isotropic…

General Relativity and Quantum Cosmology · Physics 2010-11-24 A. Tawfik , M. Wahba , H. Mansour , T. Harko

The well-known problem of wormholes in general relativity (GR) is the necessity of exotic matter, violating the Weak Energy Condition (WEC), for their support. This problem looks easier if, instead of island-like configurations, one…

General Relativity and Quantum Cosmology · Physics 2020-01-08 K. A. Bronnikov , S. V. Bolokhov , M. V. Skvortsova

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

This paper studies wormhole solutions to Einstein gravity with an arbitrary number of time dependent compact dimensions and a matter-vacuum boundary. A new gauge is utilized which is particularly suited for studies of the wormhole throat.…

General Relativity and Quantum Cosmology · Physics 2009-11-07 A. DeBenedictis , A. Das

This study investigates the possible existence of wormhole solutions with dark matter galactic halo profiles in the background of $f(Q,T)$ gravity. The primary focus of the current study is to find the significance of dark matter (DM) in…

General Physics · Physics 2024-03-01 Moreshwar Tayde , Zinnat Hassan , P. K. Sahoo

The properties of an hyperbolically-expanding wormhole are studied. Using a particular equation of state for the fluid on the wormhole throat, we reached an equation of motion for the throat that leads to a constant surface energy density…

General Relativity and Quantum Cosmology · Physics 2019-06-21 Hristu Culetu

In this study, we have conducted an analysis of traversable wormhole solutions within the framework of linear $f(Q, T) = \alpha Q + \beta T$ gravity, ensuring that all the energy conditions hold for the entire spacetime. The solutions…

General Relativity and Quantum Cosmology · Physics 2023-06-13 Moreshwar Tayde , Sayantan Ghosh , P. K. Sahoo

This thesis investigates traversable wormhole spacetimes in modified theories of gravity, where the matter at the wormhole throat is described by an anisotropic energy-momentum tensor. Wormhole solutions are constructed in the context of…

General Relativity and Quantum Cosmology · Physics 2025-04-15 Zinnat Hassan
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