Bianchi Type- I Viscous Fluid Accelerating Cosmological Models with Time Dependent Q and Λ - Term

International Journal of Mathematics Trends and Technology (IJMTT)
© 2018 by IJMTT Journal
Volume-55 Number-3
Year of Publication : 2018
Authors : Dinkar Singh Chauhan, R.S.Singh, Anirudh Pradhan


Dinkar Singh Chauhan, R.S.Singh, Anirudh Pradhan "Bianchi Type- I Viscous Fluid Accelerating Cosmological Models with Time Dependent Q and Λ - Term", International Journal of Mathematics Trends and Technology (IJMTT). V55(3):185-195 March 2018. ISSN:2231-5373. Published by Seventh Sense Research Group.

In present paper, exact solutions of Einstein's field equations are obtained in a spatially homogenous and anisotropic Bianchi type-I space-time in presence of a dissipative fluid with constant and time dependent cosmological term. Einstein's field equations are solved by considering a scale factor a(t)=tet which yields a time dependent deceleration parameter that affords a late time acceleration in the universe. The cosmological constant () is found to be a decreasing function of time and it approaches a small positive value at the present epoch which is corroborated by consequences from recent supernova Ia observations. To get the deterministic solution a barotropic equation of state together with the shear viscosity is proportional to expansion scalar, is also assumed. The physical and geometric properties of cosmological models are also discussed.

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Bianchi type-I universe, variable deceleration parameters, Dissipative fluid.