Bianchi Type-I String Cosmological Model with Bulk Viscosity and Time-Dependent Λ term
R. K. Tiwari1*, S. Sharma2**
1Department of Mathematics, Govt. Model Science College, Rewa (MP) India 2Department of Mathematics, Rayat Polytechnic College, SBS Nagar, (Punjab) India
Bianchi Type-I String Cosmological Model with Bulk Viscosity and Time-Dependent Λ term
R. K. Tiwari1*, S. Sharma2**
1Department of Mathematics, Govt. Model Science College, Rewa (MP) India 2Department of Mathematics, Rayat Polytechnic College, SBS Nagar, (Punjab) India
摘要Einstein field equations with the cosmological constant is considered in the presence of bulk viscosity in a Bianchi type-I universe. Solutions of the field equations are obtained by assuming the following conditions: the bulk viscosity is proportional to the expansion scalar ξ∝θ; the expansion scalar is proportional to shear scalar θ∝σ; and Λ is proportional to the Hubble parameter Λ∝H. The corresponding interpretations of the cosmological solutions are also discussed.
Abstract：Einstein field equations with the cosmological constant is considered in the presence of bulk viscosity in a Bianchi type-I universe. Solutions of the field equations are obtained by assuming the following conditions: the bulk viscosity is proportional to the expansion scalar ξ∝θ; the expansion scalar is proportional to shear scalar θ∝σ; and Λ is proportional to the Hubble parameter Λ∝H. The corresponding interpretations of the cosmological solutions are also discussed.
(Particle-theory and field-theory models of the early Universe (including cosmic pancakes, cosmic strings, chaotic phenomena, inflationary universe, etc.))
引用本文:
R. K. Tiwari*;S. Sharma**
. Bianchi Type-I String Cosmological Model with Bulk Viscosity and Time-Dependent Λ term[J]. 中国物理快报, 2011, 28(9): 90401-090401.
R. K. Tiwari*, S. Sharma**
. Bianchi Type-I String Cosmological Model with Bulk Viscosity and Time-Dependent Λ term. Chin. Phys. Lett., 2011, 28(9): 90401-090401.
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