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

**M. K. Singh**^{1}, **M. K. Verma**^{1}, **Shri Ram**^{1,}

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

*International Journal of Physics*, **2013** 1 (4),
pp 77-83

DOI: 10.12691/ijp-1-4-1

Received May 17, 2013; Revised June 13, 2013; Accepted June 18, 2013

Corresponding author: srmathitbhu@rediffmail.com |

## Cite This Article:

- Singh, M. K., M. K. Verma, and Shri Ram. "Anisotropic Bianchi Type-II Viscous Fluid Models with Time-Dependent Gravitational and Cosmological Constants."
*International Journal of Physics*1.4 (2013): 77-83.

- Singh, M. K. , Verma, M. K. , & Ram, S. (2013). Anisotropic Bianchi Type-II Viscous Fluid Models with Time-Dependent Gravitational and Cosmological Constants.
*International Journal of Physics*,*1*(4), 77-83.

- Singh, M. K., M. K. Verma, and Shri Ram. "Anisotropic Bianchi Type-II Viscous Fluid Models with Time-Dependent Gravitational and Cosmological Constants."
*International Journal of Physics*1, no. 4 (2013): 77-83.

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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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