Interacting Spinor and Scalar Fields in Bianchi Type I Universe Filled with Perfect Fluid: Exact Self-Consistent Solutions

Journal of Mathematical Physics

Rikhvitsky

2008

The study of a self-consistent system of interacting spinor and scalar fields within the scope of a Bianchi type I (BI) gravitational field in presence of a viscous fluid and Λ term has been carried out. The system of equations defining the evolution of the volume scale of BI universe, energy density and corresponding Hubble constant has been derived. The system in question has been thoroughly studied qualitatively. Corresponding solutions are graphically illustrated. The system in question is also studied from the view point of blow up. It has been shown that the blow up takes place only in presence of viscosity.PACS numbers: 03.65.Pm and 04.20.Ha

“…10,7,4,1], volume scale τ(t) [Figs. 11,8,5,2] and phase portrait in ν, H, ε space [Figs.12,9,6,3], for α = 4,…”

Section: Qualitative Analysis Of the Complete Systemmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Anisotropic cosmological models with spinor and scalar fields and viscous fluid in presence of a Λ term: Qualitative solutions

Journal of Mathematical Physics

Rikhvitsky

2008

“…where R is the Ricci scalar and L is the spinor and scalar field Lagrangian density chosen in the form [6] …”

Section: Fundamental Equations and General Solutionsmentioning

confidence: 99%

“…Solutions of Einstein equations coupled to a spinor and a scalar fields in BI spaces have been extensively studied by Saha and Shikin [6,7,8,9]. In the aforementioned papers, we considered spinor field in BI universe where nonlinearity occurred either due self-coupling or induced by an interacting massless scalar field.…”

Section: Introductionmentioning

confidence: 99%

Interacting Scalar And Spinor Fields In Bianchi Type I Universe Filled With Magneto-Fluid

2005

Astrophys Space Sci

Self-consistent system of spinor, scalar and BI gravitational fields in presence of magneto-fluid and Λ-term is considered. Assuming that the expansion of the BI universe is proportional to the σ 1 1 component of the shear tensor, exact solutions for the metric functions, as well as for scalar and spinor fields are obtained. For a non-positive Λ the initially anisotropic space-time becomes isotropic one in the process of expansion, whereas, for Λ > 0 an oscillatory mode of expansion of the BI model occurs.

“…Recently we studied the behavior of self-consistent nonlinear spinor field (NLSF) in a Bianchi I (B-I) universe [15] that was followed by the study of the self-consistent system of interacting spinor and scalar fields [16]. These studies were further extended to more general NLSF in presence of perfect fluid [17,18]. The aim of this paper is to extend our study with time dependent gravitational constant G and cosmological constant Λ in Einstein's equation.…”

Section: Introductionmentioning

confidence: 99%

Dirac Spinor in Bianchi-I Universe With Time-Dependent Gravitational and Cosmological Constants

2001

Mod. Phys. Lett. A

Self-consistent system of nonlinear spinor field and Bianchi I (BI) gravitational one with time dependent gravitational constant (G) and cosmological constant (Λ) has been studied. The initial and the asymptotic behaviors of the field functions and the metric one have been thoroughly investigated. Given Λ = Λ 0 /τ 2 , with τ = √ −g, G has been estimated as a function of τ . The role of perfect fluid at the initial state of expansion and asymptotical isotropization process of the initailly anisotropic universe has been elucidated.