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Related papers: Lorentzian wormholes in an emergent universe

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Dynamical wormholes in higher dimensions which admit flat emergent universe (EU) model is presented. The EU model is free from initial singularity with other observed features of the universe. The basic assumption of EU model was that the…

General Relativity and Quantum Cosmology · Physics 2020-08-11 B. C. Paul

In this paper, we construct a traversable static Lorentzian wormhole in the effective scenario of Loop Quantum Cosmology (LQC), where the field equations are modified due to the ultraviolet (UV) corrections introduced at large space-time…

General Relativity and Quantum Cosmology · Physics 2023-09-25 Rikpratik Sengupta , Shounak Ghosh , Mehedi Kalam

It is known that Lorentzian wormholes must be threaded by matter that violates the null energy condition. We phenomenologically characterize such exotic matter by a general class of microscopic scalar field Lagrangians and formulate the…

General Relativity and Quantum Cosmology · Physics 2014-11-17 C. Armendariz-Picon

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

This paper aims to investigate the possibility of physically achievable new wormhole solutions within the context of Finsler geometry by focusing on conformal motion. For this purpose, we study the barotropic linear equation of state (EoS).…

General Relativity and Quantum Cosmology · Physics 2024-01-17 Manjunath Malligawad , S. K. Narasimhamurthy , Z. Nekouee , Rajesh Kumar , Mallikarjun Y. Kumbar

It is a very well known fact that the energy conditions concerning Lorentzian wormhole (WH) solutions of Einstein equations are violated. Consequently, attempts to avoid the violation of the energy conditions constitutes one of the main…

High Energy Physics - Theory · Physics 2012-08-01 Everton M. C. Abreu , Nélio Sasaki

A specific class of flat Emergent Universe (EU) is considered and its viability is tested in view of the recent observations. Model parameters are constrained from Stern data for Hubble Parameter and Redshift ($H(z)$ vs. $z$) and from a…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 B. C. Paul , S. Ghose , P. Thakur

It has been suggested that a possible candidate for the present accelerated expansion of the Universe is ''phantom energy''. The latter possesses an equation of state of the form $\omega\equiv p/\rho<-1$, consequently violating the null…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Francisco S. N. Lobo

In this work, we investigate static and spherically symmetric traversable wormhole solutions within the framework of the extended symmetric teleparallel gravity, specifically the $\mathcal{F}(Q,\mathcal{L}_{m},\mathcal{T})$ gravity theory,…

General Relativity and Quantum Cosmology · Physics 2025-07-15 Rounak Manna , Krishna Pada Das , Ujjal Debnath

In this study, we investigate traversable wormholes within the framework of Einstein-Euler-Heisenberg (EEH) nonlinear electrodynamics. By employing the Einstein field equations with quantum corrections from the Euler-Heisenberg Lagrangian,…

General Relativity and Quantum Cosmology · Physics 2025-05-27 Phongpichit Channuie , Allah Ditta , Narakorn Kaewkhao , Ali Övgün

We discuss the properties of Lorentzian wormholes in dilatonic Einstein-Gauss-Bonnet theory in four spacetime dimensions. These wormholes do not need any form of exotic matter for their existence. A subset of these wormholes is shown to be…

High Energy Physics - Theory · Physics 2015-03-19 Panagiota Kanti , Burkhard Kleihaus , Jutta Kunz

Firstly, we review the pointwise and averaged energy conditions, the quantum inequality and the notion of the ``volume integral quantifier'', which provides a measure of the ``total amount'' of energy condition violating matter. Secondly,…

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

We study a composition of normal and exotic matter which is required for a flat Emergent Universe scenario permitted by the equation of state (EOS)($p=A\rho-B\rho^{1/2}$) and predict the range of the permissible values for the parameters…

Cosmology and Nongalactic Astrophysics · Physics 2013-02-27 B. C. Paul , P. Thakur , S. Ghose

We have investigated the non-static Lorentzian Wormhole model in presence of anisotropic pressure. We have presented some exact solutions of Einstein equations for anisotropic pressure case. Introducing two EoS parameters we have shown that…

General Physics · Physics 2014-11-06 Ujjal Debnath , Mubasher Jamil , R. Myrzakulov , M. Akbar

Wormholes are non-trivial topological structures that arise as exact solutions to Einstein's field equations, theoretically connecting distinct regions of spacetime via a throat-like geometry. While static traversable wormholes necessarily…

General Relativity and Quantum Cosmology · Physics 2025-07-22 Mahdi Kord Zangeneh , Francisco S. N. Lobo

A possible candidate for the present accelerated expansion of the Universe is ''phantom energy'', which possesses an equation of state of the form $\omega\equiv p/\rho<-1$, consequently violating the null energy condition. As this is the…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Francisco S. N. Lobo

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

In this paper we study the possibility of sustaining an evolving wormhole via exotic matter made of phantom energy in the presence of a cosmological constant. We derive analytical evolving wormhole geometries by supposing that the radial…

General Relativity and Quantum Cosmology · Physics 2009-01-16 Mauricio Cataldo , Sergio del Campo , Paul Minning , Patricio Salgado

Traversable wormhole solutions in General Relativity require exotic matter sources that violate the null energy condition (NEC), and such behavior maybe avoided in modified gravity. In this study, we analyze the energy conditions for…

General Relativity and Quantum Cosmology · Physics 2023-01-25 Anshuman Baruah , Parangam Goswami , Atri Deshamukhya

Traversable wormholes necessarily require violations of the averaged null energy condition; this being the definition of ``exotic matter''. However, the theorems which guarantee the energy condition violation are remarkably silent when it…

General Relativity and Quantum Cosmology · Physics 2011-07-18 Matt Visser , Sayan Kar , Naresh Dadhich
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