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We are interested in formulating a viscous model of the universe based on TheBianchi Type IV algebra. We first begin by considering a congruence of fluidlines in spacetime, upon which, analyzing their propagation behaviour, wederive the famous Raychaudhuri equation, but, in the context of viscous fluids.We will then go through in great detail the topological and algebraic structureof a Bianchi Type IV algebra, by which we will derive the correspondingstructure and constraint equations. From this, we will look at The Einsteinfield equations in the context of orthonormal frames, and derive the resultingdynamical equations: The \emph{Raychaudhuri Equation}, \emph{generalizedFriedmann equation}, \emph{shear propagation equations}, and a set ofnon-trivial constraint equations. We show that for cases in which the bulkviscous pressure is significantly larger than the shear viscosity, thiscosmological model isotropizes asymptotically to the present-day universe. Wefinally conclude by discussing The Penrose-Hawking singularity theorem, andshow that the viscous universe under consideration necessarily emerged from apast singularity point.

A Bianchi Type IV Viscous Fluid Model of The Early Universe