Open Access Peer-reviewed

Anisotropic Bianchi Type-II Viscous Fluid Models with Time-Dependent Gravitational and Cosmological Constants

M. K. Singh1, M. K. Verma1, Shri Ram1,

1Department of Applied Mathematics, Indian Institute of Technology, Banaras Hindu University, Varanasi, India

International Journal of Physics. 2013, 1(4), 77-83. DOI: 10.12691/ijp-1-4-1
Published online: August 25, 2017


This paper deals with totally anisotropic Bianchi type-II cosmological models filled with a bulk viscous fluid in the presence of time-varying gravitational and cosmological constants. Exact solutions of the field equations are obtained by applying a special law of variation for Hubble’s parameter which yields a constant value of the deceleration parameter. Two different physically viable models of the universe are presented in two types of cosmologies, one with power-law expansion and other one with exponential expansion. Cosmological model with power-law expansion has an initial big-bang type singularity at t = 0, whereas the model with exponential expansion has a singularity in infinite past. The physical and dynamical properties of the models are discussed.


Bianchi II, bulk viscosity, gravitational constant, cosmological constant
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