中文
相关论文

相关论文: Bianchi Type-I Cosmological Models with Variable G…

200 篇论文

We consider a Bianchi type-I Polytropic bulk viscous fluid cosmological model with variable G and {\Lambda}. To get a deterministic model, we assume some conditions of A, B, C, and polytropic relation to find the results. physical…

综合物理 · 物理学 2014-03-11 Rishi Kumar Tiwari , Mukesh Sharma , Sonia Sharma

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…

广义相对论与量子宇宙学 · 物理学 2018-04-10 Ben David Normann , Sigbjørn Hervik , Angelo Ricciardone , Mikjel Thorsrud

Bianchi type V bulk viscous fluid cosmological models are investigated. Using a generation technique (Camci {\it et al.}, 2001), it is shown that the Einstein's field equations are solvable for any arbitrary cosmic scale function. The…

广义相对论与量子宇宙学 · 物理学 2009-07-23 Anirudh Pradhan , Vandana Rai , R. S. Singh

We study the anisotropic Bianchi type-I cosmological model at late times, taking into account quantum gravitational corrections in the formalism of the exact renormalization group flow of the effective average action for gravity. The…

广义相对论与量子宇宙学 · 物理学 2020-02-24 Rituparna Mandal , Sunandan Gangopadhyay , Amitabha Lahiri

We show under the assumption of small data that solutions to the Einstein-Vlasov system with a pure magnetic field and Bianchi I symmetry isotropise and tend to dust solutions. We also obtain the decay rates for the main variables. This…

广义相对论与量子宇宙学 · 物理学 2024-06-18 Ho Lee , Ernesto Nungesser

We consider the dynamics of a Bianchi type I spacetime in the presence of dilaton and magnetic fields. The general solution of the Einstein-Maxwell dilaton field equations can be obtained in an exact parametric form. Depending on the…

广义相对论与量子宇宙学 · 物理学 2009-11-07 T. Harko , M. K. Mak

In this paper we study the evolution of a LRS Bianchi I Universe, filled with a bulk viscous cosmological fluid in the presence of time varying constants "but" taking into account the effects of a c-variable into the curvature tensor. We…

广义相对论与量子宇宙学 · 物理学 2009-11-10 J. A. Belinchón

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…

广义相对论与量子宇宙学 · 物理学 2007-05-23 Nguyen Hong Chuong , Nguyen Van Hoang

Self-consistent solutions to the spinor, scalar and BI gravitational field equations are obtained. The problems of initial singularity and asymptotically isotropization process of the initially anisotropic space-time are studied. It is also…

广义相对论与量子宇宙学 · 物理学 2007-05-23 Bijan Saha

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…

广义相对论与量子宇宙学 · 物理学 2024-10-29 David Brizuela , Sara F. Uria

A cosmological model describing the evolution of $n$ Einstein spaces $(n>1)$ with $m$-component perfect-fluid matter is considered. When all spaces are Ricci-flat and for any $\alpha$-th component the pressures in all spaces are…

广义相对论与量子宇宙学 · 物理学 2011-04-20 V. D. Ivashchuk , V. N. Melnikov

Locally rotationally symmetric (L.R.S.) Bianchi type II stiff fluid cosmological model is investigated. To get the deterministic model of the universe, we have assumed a condition $A=B^{m}$ between metric potentials $A,~B$ where $n$ is the…

广义相对论与量子宇宙学 · 物理学 2011-05-26 Hassan Amirhashchi

Bianchi type I massive string cosmological model with magnetic field of barotropic perfect fluid distribution through the techniques used by Latelier and Stachel, is investigated. To get the deterministic model of the universe, it is…

广义相对论与量子宇宙学 · 物理学 2008-11-26 Raj Bali , Umesh Kumar Pareek , Anirudh Pradhan

We consider the dynamics of a barotropic cosmological fluid in an anisotropic, Bianchi type I space-time in Eddington-inspired Born-Infeld (EiBI) gravity. By assuming an isotropic pressure distribution, we obtain the general solution of the…

广义相对论与量子宇宙学 · 物理学 2014-10-30 Tiberiu Harko , Francisco S. N. Lobo , M. K. Mak

In this paper we are to study homogeneous and anisotropic Bianchi type-V universe in presence of bulk viscous fluid source of matter with time function gravitational constant G and cosmological term lambda. The viscosity coefficient is…

广义相对论与量子宇宙学 · 物理学 2023-05-19 Nawsad Ali

Einstein's field equations for stationary Bianchi type II models with a perfect fluid source are investigated. The field equations are rewritten as a system of autonomous first order differential equations. Dimensionless variables are…

广义相对论与量子宇宙学 · 物理学 2009-10-30 Ulf S. Nilsson , C. Uggla

A self-consistent system of interacting spinor and scalar fields is considered within the scope of Bianchi type VI cosmological model filled with a perfect fluid. The contribution of the cosmological constant ($\Lambda$-term) is taken into…

广义相对论与量子宇宙学 · 物理学 2007-05-23 Bijan Saha

We consider the dynamics of a causal bulk viscous cosmological fluid filled constantly decelerating Bianchi type I space-time. The matter component of the Universe is assumed to satisfy a linear barotropic equation of state and the state…

广义相对论与量子宇宙学 · 物理学 2008-11-26 M. K. Mak , T. Harko

We study several cosmological models with Bianchi VI_0&III symmetries under the self-similar approach. We find new solutions for the "classical" perfect fluid model as well as for the vacuum model although they are really restrictive for…

广义相对论与量子宇宙学 · 物理学 2009-08-12 José Antonio Belinchón

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…

广义相对论与量子宇宙学 · 物理学 2015-05-01 Bijan Saha