فهرست مقالات Bianchi type

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  1 - String cosmological models with bulk viscosity in Nordtvedt's general scalar-tensor theory of gravitation
  Uma Maheswara Rao Velagapudi Neelima Davuluri
  10.1186/2251-7235-7-50
  AbstractWe have obtained and presented spatially homogeneous Bianchi types II, VIII, and IX string cosmological models with bulk viscosity in Nordtvedt's (Astrophys. J. 161:1059, 1970) general scalar-tensor theory of gravitation with the help of a special case proposed چکیده کامل

  AbstractWe have obtained and presented spatially homogeneous Bianchi types II, VIII, and IX string cosmological models with bulk viscosity in Nordtvedt's (Astrophys. J. 161:1059, 1970) general scalar-tensor theory of gravitation with the help of a special case proposed by Schwinger. It is observed that only the bulk viscous cosmological model exists in the case of Bianchi type IX universe. Some important features of the models, thus obtained, have been discussed. پرونده مقاله
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  2 - Accelerating Bianchi type-VI0 bulk viscous cosmological models in Lyra geometry
  A. Asgar M. Ansari
  10.1007/s40094-014-0151-7
  AbstractThe present study deals with spatially homogeneous and totally anisotropic Bianchi type-VI0 bulk viscous cosmological models in Lyra geometry. The Einstein’s field equations have been solved exactly by taking the shear (σ) in the model proportional to expansion چکیده کامل

  AbstractThe present study deals with spatially homogeneous and totally anisotropic Bianchi type-VI0 bulk viscous cosmological models in Lyra geometry. The Einstein’s field equations have been solved exactly by taking the shear (σ) in the model proportional to expansion scalar (θ) which leads to A = Bn, where A and B are metric functions and n is a positive constant (n > 1). We also adopt a condition ζθ=L (constant) where ζ is the coefficient of bulk viscosity. It has been found that the displacement vector (β) is a decreasing function of time and it approaches to a small positive value at late time which is supported by recent observations. It is also found that the distance modulus curve of derived model matches with observations perfectly. پرونده مقاله