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Related papers: Slowly evolving noncommutative-geometry wormholes

200 papers

We study effects of noncommutativity on the phase space generated by a non-minimal scalar field which is conformally coupled to the background curvature in an isotropic and homogeneous FRW cosmology. These effects are considered in two…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Behrooz Malekolkalami , Mehrdad Farhoudi

We analyze the nonlinear evolution of spherically symmetric wormhole solutions coupled to a massless ghost scalar field using numerical methods. In a previous article we have shown that static wormholes with these properties are unstable…

General Relativity and Quantum Cosmology · Physics 2008-12-25 J. A. Gonzalez , F. S. Guzman , O. Sarbach

In this work, we study the rotating wormhole geometries supported by a three-form field. We demonstrate for particular choices of parameters that it is possible for the matter fields threading the wormhole to satisfy the null and weak…

General Relativity and Quantum Cosmology · Physics 2024-01-18 Takol Tangphati , Butsayapat Chaihao , Daris Samart , Phongpichit Channuie , Davood Momeni

We revisit the evolution of the scale factor in a flat FRW spacetime with a new generalized decay rule for the dynamic $\Lambda$-term under modified theories of gravity. It analyses certain cosmological parameters and examines their…

General Physics · Physics 2021-08-02 Anirudh Pradhan , De Avik , Tee How Loo , D. C. Maurya

In this paper we review some properties for the evolving wormhole solution of Einstein equations coupled with nonlinear electrodynamics. We integrate the geodesic equations in the effective geometry obeyed by photons; we check out the weak…

General Relativity and Quantum Cosmology · Physics 2010-01-08 Aaron V. B. Arellano , Nora Breton , Ricardo Garcia-Salcedo

In this paper, we explore static spherically symmetric wormhole solutions in the framework of $n$-dimensional Einstein Gauss-Bonnet gravity. Our objective is to find out wormhole solutions that satisfy energy conditions. For this purpose,…

General Physics · Physics 2016-11-02 Shamaila Rani , Abdul Jawad

It is shown that any mathematical solution for null electromagnetic field knots in flat spacetime is also a null field knotted solution for cosmological electromagnetic fields. This is obtained by replacing the time $t\rightarrow \tau=\int…

General Relativity and Quantum Cosmology · Physics 2024-03-26 Sergio A. Hojman , Felipe A. Asenjo

We study the cosmological evolution with nonsingular branes generated by a bulk scalar field coupled to gravity. The specific setup investigated leads to branes with a time-dependent warp factor. We calculate the effective Hubble parameter…

General Relativity and Quantum Cosmology · Physics 2017-11-22 Paulo Michel L. T. da Silva , Alvaro de Souza Dutra , Julio Marny Hoff da Silva

Some novel regular spacetimes are considered that show a non-stationary wormhole structure. A Simpson-Visser-like procedure is applied to reconstruct these regular spacetimes, free of time-like and space-like singularities. Such a procedure…

General Relativity and Quantum Cosmology · Physics 2025-08-13 G. Alencar , R. Dárlla , Shin'ichi Nojiri , Sergei D. Odintsov , Diego Sáez-Chillón Gómez

Recently it has been shown by Almheiri and Lin [1] that the reconstruction of black-hole interior is sensitive to knowing the exact coupling of the boundary theory even if the coupling is irrelevant. This motivates us to enlarge the set of…

High Energy Physics - Theory · Physics 2022-10-05 Diptarka Das , Sridip Pal , Anurag Sarkar

The aim of this manuscript is to study the traversable wormhole (WH) geometries in the curvature matter coupling gravity. We investigate static spherically symmetric Morris-Thorne WHs within the context of $f(R,L_m)$ gravity. To accomplish…

General Relativity and Quantum Cosmology · Physics 2023-05-26 V. Venkatesha , N. S. Kavya , P. K. Sahoo

This paper examines wormhole geometries in the context of $f(Q,T)$ gravity under the background of non-commutative distributions. We discuss the analytical solutions assuming spherical symmetry and the presence of conformal Killing vectors,…

General Relativity and Quantum Cosmology · Physics 2024-03-22 Moreshwar Tayde , Zinnat Hassan , P. K. Sahoo

An explicit and complete set of constants of the motion are constructed algorithmically for Friedmann-Lema\^{i}tre-Robertson-Walker (FLRW) models consisting of an arbitrary number of non-interacting species. The inheritance of constants of…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Kayll Lake

We present here analytical solutions of General Relativity that describe evolving wormholes with a non-constant redshift function. We show that the matter that threads these wormholes is not necessarily exotic. Finally, we investigate some…

General Relativity and Quantum Cosmology · Physics 2009-10-30 Luis A. Anchordoqui , Diego F. Torres , Marta L. Trobo , Santiago E. Perez Bergliaffa

In this work we propose the modelling of static wormholes within the $f(R,T)$ extended theory of gravity perspective. We present some models of wormholes, which are constructed from different hypothesis for their matter content, i.e.,…

General Relativity and Quantum Cosmology · Physics 2017-09-06 P. H. R. S. Moraes , P. K. Sahoo

We explore the possibility of dynamic wormhole geometries, within the context of nonlinear electrodynamics. The Einstein field equation imposes a contracting wormhole solution and the obedience of the weak energy condition. Furthermore, in…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Aaron V. B. Arellano , Francisco S. N. Lobo

We derive noncommutative Einstein equations for abelian twists and their solutions in consistently symmetry reduced sectors, corresponding to twisted FRW cosmology and Schwarzschild black holes. While some of these solutions must be…

High Energy Physics - Theory · Physics 2009-10-20 Thorsten Ohl , Alexander Schenkel

In this article, we investigate asymptotically flat non-exotic traversable wormhole geometries within the King and Dekel-Zhao dark matter halos in the framework of $f(R, L_m)$ gravity. Two functional forms of the theory are considered:…

General Relativity and Quantum Cosmology · Physics 2026-01-21 Susmita Sarkar , Nayan Sarkar , Abdelmalek Bouzenada , Farook Rahaman

We study the classical and quantum wormholes for a flat {\it Euclidean} Friedmann-Robertson-Walker metric with a perfect fluid including an ordinary matter source plus a source playing the role of dark energy (decaying cosmological term).…

General Relativity and Quantum Cosmology · Physics 2009-03-24 F. Darabi

While the use of numerical general relativity for modeling astrophysical phenomena and compact objects is commonplace, the application to cosmological scenarios is only just beginning. Here, we examine the expansion of a spacetime using the…

General Relativity and Quantum Cosmology · Physics 2016-06-27 John T. Giblin , James B. Mertens , Glenn D. Starkman