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Related papers: Self-similar Bianchi models: I. Class A models

200 papers

In this paper we give, for the first time, a complete description of the dynamics of tilted spatially homogeneous cosmologies of Bianchi type II. The source is assumed to be a perfect fluid with equation of state $p = (\gamma -1) \mu$,…

General Relativity and Quantum Cosmology · Physics 2015-06-25 C. G. Hewitt , R. Bridson , J. Wainwright

The purpose of this paper is to find conformal vector fields of some perfect fluid Kantowski-Sachs and Bianchi type III space-times in the f(R) theory of gravity using direct integration technique. In this study there exists only eight…

General Relativity and Quantum Cosmology · Physics 2019-04-17 Ghulam Shabbir , Fiaz Hussain , A. H. Kara , Muhammad Ramzan

In this paper, we have investigated Bianchi type VIh, II and III cosmological model with wet dark fluid in scale invariant theory of gravity, where the matter field is in the form of perfect fluid and with a time dependent gauge function…

General Relativity and Quantum Cosmology · Physics 2017-02-01 B. Mishra , P. K. Sahoo

A brief summary of results on kinematic self-similarities in general relativity is given. Attention is focussed on locally rotationally symmetric models admitting kinematic self-similar vectors. Coordinate expressions for the metric and the…

General Relativity and Quantum Cosmology · Physics 2016-08-31 A. M. Sintes

We consider a class of inhomogeneous self-similar cosmological models in which the perfect fluid flow is tangential to the orbits of a three-parameter similarity group. We restrict the similarity group to possess both an Abelian $G_{2}$,…

General Relativity and Quantum Cosmology · Physics 2021-08-11 Sepehr Rashidi , C. G. Hewitt , Benoit Charbonneau

The dynamics of a class of cosmological models with collisionless matter and four Killing vectors is studied in detail and compared with that of corresponding perfect fluid models. In many cases it is possible to identify asymptotic states…

General Relativity and Quantum Cosmology · Physics 2009-10-31 A. D. Rendall , K. P. Tod

A spatially homogeneous Bianchi type VI0 model containing a viscous fluid in the presence of an axial magnetic field has been studied. A barotropic equation of state together with a pair of linear relations among the square root of matter…

General Relativity and Quantum Cosmology · Physics 2021-05-18 Marcelo Byrro Ribeiro , Abhik Kumar Sanyal

We derive exact solutions to the vacuum Einstein field equations in 5D, under the assumption that (i) the line element in 5D possesses self-similar symmetry, in the classical understanding of Sedov, Taub and Zeldovich, and that (ii) the…

General Relativity and Quantum Cosmology · Physics 2009-03-12 J. Ponce de Leon

Within the framework of the minimum quadratic Poincare gauge theory of gravity in the Riemann-Cartan spacetime the dynamics of homogeneous anisotropic Bianchi types I-IX spinning-fluid cosmological models is investigated. A basic equation…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Nguyen Hong Chuong , Nguyen Van Hoang

We consider the late time behaviour of non-tilted perfect fluid Bianchi VII_0 models when the source is a radiation fluid, thereby completing the analysis of the Bianchi VII_0 models initiated by Wainwright et al in a recent paper. The…

General Relativity and Quantum Cosmology · Physics 2009-10-31 U S Nilsson , M J Hancock , J Wainwright

In this paper we present the noncommutative Bianchi Class A cosmological models coupled to barotropic perfect fluid. The commutative and noncommutative quantum solution to the Wheeler-DeWitt equation for any factor ordering, to the…

General Relativity and Quantum Cosmology · Physics 2008-11-26 M. Aguero , J. A. Aguilar S. , C. Ortiz , M. Sabido , J. Socorro

We show several kinematical properties that are intrinsic to the Bianchi models with compact spatial sections. Especially, with spacelike hypersurfaces being closed, (A) no anisotropic expansion is allowed for Bianchi type V and…

General Relativity and Quantum Cosmology · Physics 2010-04-06 Y. Fujiwara , H. Ishihara , H. Kodama

In this paper we study the future asymptotics of spatially homogeneous Bianchi type II cosmologies with a tilted perfect fluid with a linear equation of state. By means of Hamiltonian methods we first find a monotone function for a special…

General Relativity and Quantum Cosmology · Physics 2011-12-08 Sigbjorn Hervik , Woei Chet Lim , Patrik Sandin , Claes Uggla

Global symmetries of the string effective action are employed to generate tilted, homogeneous Bianchi type VI_h string cosmologies from a previously known stiff perfect fluid solution to Einstein gravity. The dilaton field is not constant…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Dominic Clancy , Alexander Feinstein , James E. Lidsey , Reza Tavakol

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

We consider the Bianchi I geometry coupled to several species of comoving barotropic perfect fluids with a linear equation of state in the context of general relativity. The solution of the dynamics can be reduced to a quadrature, which can…

General Relativity and Quantum Cosmology · Physics 2024-10-29 David Brizuela , Sara F. Uria

In this paper the dynamics of free gauge fields in Bianchi type I-VII$_{h}$ space-times is investigated. The general equations for a matter sector consisting of a $p$-form field strength ($p\,\in\,\{1,3\}$), a cosmological constant…

General Relativity and Quantum Cosmology · Physics 2018-04-10 Ben David Normann , Sigbjørn Hervik , Angelo Ricciardone , Mikjel Thorsrud

In this paper, we study the behavior of perfect fluid and massless scalar field for homogeneous and anisotropic Bianchi type I universe model in $f(R,T)$ gravity, where $R$ is the Ricci scalar and $T$ is the trace of the energy-momentum…

General Relativity and Quantum Cosmology · Physics 2015-06-12 Muhammad Sharif , Muhammad Zubair

We consider a self-consistent system of Bianchi type-I (BI) gravitational field and a binary mixture of perfect fluid and dark energy. The perfect fluid is taken to be the one obeying the usual equation of state, i.e., $p = \zeta \ve$, with…

General Relativity and Quantum Cosmology · Physics 2015-05-01 Bijan Saha

We consider a self-consistent system of spinor and scalar fields within the framework of a Bianchi type I gravitational field filled with viscous fluid in presence of a $\Lambda$ term. Exact self-consistent solutions to the corresponding…

General Relativity and Quantum Cosmology · Physics 2019-04-22 Bijan Saha