Polytropic Bulk Viscous Cosmological Model with Variable G and Λ


We consider a Bianchi type-I Polytropic bulk viscous fluid cosmological model with variable G and Λ. To get a deterministic model, it is assumed that and , , , where is the pressure, ρ is the energy density, η is the coefficient of bulk viscosity, α, k, γ and ηo are constants, H is Hubble constant, where k1 > 0, k2 > 0. The solution obtained lead to inflationary phase and the results obtained match with the observations [31] [32]. The case n = 1 for α = 1 is also discussed, relating the results with the observations.

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Tiwari, R. , Sharma, M. and Sharma, S. (2014) Polytropic Bulk Viscous Cosmological Model with Variable G and Λ. Open Access Library Journal, 1, 1-8. doi: 10.4236/oalib.1100729.

Conflicts of Interest

The authors declare no conflicts of interest.


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