English
Related papers

Related papers: Anisotropic Bouncing Scenario in $F(X)-V(\phi)$ mo…

200 papers

Static spherically symmetric anisotropic source has been studied for the Einstein-Maxwell field equations assuming the erstwhile cosmological constant $ \Lambda $ to be a space-variable scalar, viz., $ \Lambda = \Lambda(r) $. Two cases have…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Saibal Ray , Sumana Bhadra , Anand S. Sengupta

Astronomical observations suggest that the Universe may be anisotropic on the largest scales. In order to model this situation, we develop a new approach to cosmology that allows for large-scale anisotropy to emerge from the growth of…

General Relativity and Quantum Cosmology · Physics 2023-06-26 Theodore Anton , Timothy Clifton

Some new exact solutions of Einstein's field equations in a spatially homogeneous and anisotropic Bianchi type-V space-time with minimally interaction of perfect fluid and dark energy components have been obtained. To prevail the…

General Physics · Physics 2011-10-06 Anirudh Pradhan , H. Amirhashchi

In this paper we study the evolution of spatially homogeneous and anisotropic Bianchi type-I Universe models with the cosmological constant, \Lambda, and filled with nonlinear viscous fluid. The dynamical equations for these models are…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Nouraddin Mostafapoor , Oyvind Gron

This manuscript is based on an investigation of bouncing cosmology in a 4D Einstein Gauss-Bonnet gravity. Various bouncing models such as symmetric bounce, matter bounce, super bounce, and oscillatory bounce have been examined. Expressions…

General Relativity and Quantum Cosmology · Physics 2023-06-16 M. Zubair , Mushayydha Farooq

In this work a class of interior solution for Einstein field equations corresponding to a spherically symmetric anisotropic fluid sphere has been obtained under the assumption that the cosmological constant is spatially variable. The…

General Relativity and Quantum Cosmology · Physics 2011-03-07 R. N. Tiwari , Saibal Ray

We prove well-posedness of the initial value problem for the Einstein equations for spatially-homogeneous cosmologies with data at an isotropic cosmological singularity, for which the matter content is either a cosmological constant with…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Paul Tod

In this paper, we describe the dynamics of a Bianchi Type V vacuum universe with an arbitrary cosmological constant. We begin by using an orthonormal frame approach to write Einstein's field equations as a coupled system of first-order…

General Relativity and Quantum Cosmology · Physics 2017-04-12 Ikjyot Singh Kohli

By quantising the background as well as the perturbations in a simple one fluid model, we show that there exists an ambiguity in the choice of relevant variables, potentially leading to incompatible observational physical predictions. In a…

General Relativity and Quantum Cosmology · Physics 2023-10-25 Jaime de Cabo Martin , Przemysław Małkiewicz , Patrick Peter

We explore dynamics of cosmological models with bounce solutions evolving on a spatially flat Friedmann-Lemaitre-Robertson-Walker background. We consider cosmological models that contain the Hilbert-Einstein curvature term, the induced…

General Relativity and Quantum Cosmology · Physics 2016-12-08 Ekaterina O. Pozdeeva , Maria A. Skugoreva , Alexey V. Toporensky , Sergey Yu. Vernov

In this paper we provide approximate analytical analysis of stability of nonsingular inflationary chaotic-type cosmological models. Initial conditions for nonsingular solutions at the bounce correspond to dominance of potential part of the…

Astrophysics · Physics 2009-11-10 G. V. Vereshchagin

The dynamics of cosmological models with isotropic matter sources (perfect fluids) is extensively studied in the literature; in comparison, the dynamics of cosmological models with anisotropic matter sources is not. In this paper we…

General Relativity and Quantum Cosmology · Physics 2011-02-16 Simone Calogero , J. Mark Heinzle

In the scope of the nonlinear massive gravity, we study fixed points of evolution equations for a Bianchi type--I universe. We find a new attractor solution with non-vanishing anisotropy, on which the physical metric is isotropic but the…

High Energy Physics - Theory · Physics 2012-10-17 A. Emir Gumrukcuoglu , Chunshan Lin , Shinji Mukohyama

We consider alternative inflationary cosmologies in massive gravity with degenerate reference metrics and study the feasibilities of the emergent universe scenario, bouncing and cyclic universes. We focus on the construction of the Einstein…

General Relativity and Quantum Cosmology · Physics 2019-05-28 Shou-Long Li , H. Lü , Hao Wei , Puxun Wu , Hongwei Yu

Anisotropic cosmological spacetimes are constructed from spherically symmetric solutions to Einstein's equations coupled to nonlinear electrodynamics and a positive cosmological constant. This is accomplished by finding solutions in which…

High Energy Physics - Theory · Physics 2011-07-19 Dan N. Vollick

The stability criteria for spatially flat homogeneous and isotropic cosmological dynamical system is investigated with the interaction of a scalar field endowed with a perfect fluid.In this paper, we depict the dynamical system perspective…

General Relativity and Quantum Cosmology · Physics 2021-01-25 S. Surendra Singh , Chingtham Sonia

Mathematical modeling of gravitating configurations of physical fields is one of the priority directions of the modern theory of gravity. Most of the exact solutions constructed within the framework of the general relativity are static or…

General Relativity and Quantum Cosmology · Physics 2019-12-03 Ju V Tchemarina , E G Alekseeva , A N Tsirulev , N K Nuraliev

This paper uses the definition of complexity for a static spherically symmetric spacetime and extends it to the case of charged distribution. We formulate the Einstein-Maxwell field equations corresponding to the anisotropic interior and…

General Relativity and Quantum Cosmology · Physics 2023-06-02 M. Sharif , Tayyab Naseer

The cosmological dynamics in the early universe are investigated to explore the possibility of the sign reversal of the Hubble parameter as a key feature of non-singular bouncing cosmological solutions in higher-order torsion gravity. The…

General Relativity and Quantum Cosmology · Physics 2026-03-31 Adnan Malik , Aimen Rauf , Kazuharu Bamba , Wenbin Lin , Fatemah Mofarreh

We explore the possibility of realizing a non-singular bounce in the early universe within the framework of modified gravity with spacetime torsion. In Einstein Cartan theory, torsion is embedded in the spacetime by adding an antisymmetric…

General Relativity and Quantum Cosmology · Physics 2026-01-21 Sonej Alam , Somasri Sen , Soumitra Sengupta