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Bulk Viscous Solutions to the Field Equations and the Deceleration Parameter-Revisited

Anirudh Pradhan·Aotemshi I
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Abstract

We utilise a form for the Hubble parameter to generate a number of solutions to the Einstein field equations with variable cosmological constant and variable gravitational constant in the presence of a bulk viscous fluid. The Hubble law utilised yields a constant value for the deceleration parameter. A new class of solutions is presented in the Robertson-Walker spacetimes. The coefficient of bulk viscosity is assumed to be a power function of the mass density. For a class of solutions, the deceleration parameter is negative which is consistent with the supernovae Ia observations.

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Anirudh Pradhan, Aotemshi I. 2002-07-04. Bulk Viscous Solutions to the Field Equations and the Deceleration Parameter-Revisited. https://doi.org/10.1142/s0218271802002402

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