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Related papers: Wormholes in a viscous universe

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We construct traversable wormholes by starting with simple four-dimensional classical solutions respecting the null energy condition and containing a pair of oppositely charged black holes connected by a non-traversable wormhole. We then…

High Energy Physics - Theory · Physics 2020-01-03 Zicao Fu , Brianna Grado-White , Donald Marolf

We derive a general formalism for bulk viscous solutions of the energy-conservation-equation for $\rho(a,\zeta)$, both for a single-component and a multicomponent fluid in the Friedmann universe. For our purposes these general solutions…

General Relativity and Quantum Cosmology · Physics 2016-06-03 Ben David Normann , Iver Brevik

The bulk viscosity is introduced to model unified dark matter. The viscous unified model assumes the universe is filled with a single fluid with the bulk viscosity. We review the general framework of the viscous cosmology. The Hubble…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Xu Dou , Xin-He Meng

Bulk viscosity in cold dark matter is an appealing feature that introduces distinctive phenomenological effects in the cosmological setting as compared to the $\Lambda$CDM model. Under this view, we propose a general parametrization of the…

General Relativity and Quantum Cosmology · Physics 2023-08-24 Gabriel Gómez , Guillermo Palma , Ángel Rincón , Norman Cruz , Esteban González

We utilise a form for the Hubble parameter to generate a number of solutions to the Einstein field equations with variable cosmological constant and variable gravitational constant in the presence of a bulk viscous fluid. The Hubble law…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Anirudh Pradhan , Aotemshi I

In this paper, we investigate static spherically symmetric wormhole solutions in the background of $F(T,T_\mathcal{G})$ gravity ($T$ is the torsion scalar and $T_{\mathcal{G}}$ represents teleparallel equivalent of the Gauss-Bonnet term).…

General Relativity and Quantum Cosmology · Physics 2018-05-31 M. Sharif , Kanwal Nazir

In this paper, we explore higher-dimensional asymptotically flat wormhole geometries in the framework of Gauss-Bonnet (GB) gravity and investigate the effects of the GB term, by considering a specific radial-dependent redshift function and…

General Relativity and Quantum Cosmology · Physics 2015-04-06 Mohammad Reza Mehdizadeh , Mahdi Kord Zangeneh , Francisco S. N. Lobo

The statefinder diagnostic pair is adopted to differentiate viscous cosmology models and it is found that the trajectories of these viscous cosmology models on the statefinder pair $s-r$ plane are quite different from those of the…

Astrophysics · Physics 2009-11-13 M. Hu , Xin He Meng

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

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 this study we present evolving wormhole configurations in third-order {Lovelock} gravity and investigate the possibility that these solutions satisfy the energy conditions. Using a generalized Friedmann-Robertson-Walker spacetime, we…

General Relativity and Quantum Cosmology · Physics 2021-12-01 Mohammad Reza Mehdizadeh , Amir Hadi Ziaie

In this letter, we investigate the traversable wormholes in the holographic dark energy (HDE) model constrained by the modern astronomical observations. First of all, we constrain the HDE model by adopting different data-sets, explore the…

General Relativity and Quantum Cosmology · Physics 2016-09-21 Deng Wang , Xin-he Meng

Running vacuum models and viscous dark matter scenarios beyond perfect fluid idealization are two appealing theoretical strategies that have been separately studied as alternatives to solve some problems rooted in the $\Lambda$CDM…

General Relativity and Quantum Cosmology · Physics 2023-04-26 Norman Cruz , Gabriel Gomez , Esteban Gonzalez , Guillermo Palma , Angel Rincon

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

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

This study explores the potential existence of traversable wormholes influenced by a global monopole charge within the $f(Q)$ gravity framework. To elucidate the characteristics of these wormholes, we conducted a comprehensive analysis of…

General Relativity and Quantum Cosmology · Physics 2024-06-26 Moreshwar Tayde , P. K. Sahoo

We explore the possibility of traversable wormhole formation in the dark matter halos in the context of $f(Q)$ gravity. We obtain the exact wormhole solutions with anisotropic matter source based on the Bose-Einstein condensate,…

General Relativity and Quantum Cosmology · Physics 2024-10-28 G. Mustafa , Zinnat Hassan , P. K. Sahoo

We investigate if theories yielding bouncing cosmological models also generate wormhole solutions. We show that two of them present sensible traversable static wormhole solutions, while for the third possibility such solutions are absent.

General Relativity and Quantum Cosmology · Physics 2014-10-31 N. Pinto-Neto , F. P. Poulis , J. M. Salim

Bulk viscosity is the only viscous influence that can change the background dynamics in a homogeneous and isotropic universe. In the present work, we analyze the bulk viscous cosmological model with the bulk viscosity coefficient of the…

General Relativity and Quantum Cosmology · Physics 2021-12-13 Gaurav Gadbail , Simran Arora , P. K. Sahoo

In this work, we find exact wormhole solutions in the context of noncommutative geometry, and further explore their physical properties and characteristics. The energy density of these wormhole geometries is a smeared and particle-like…

General Relativity and Quantum Cosmology · Physics 2008-12-23 Remo Garattini , Francisco S. N. Lobo
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