Bianchi II, VIII, and IX viscous fluid cosmology

Understand

In this paper we study the exact solutions for a viscous fluid distribution in Bianchi II, VIII, and IX models.

• The metric is simplified by assuming a relationship between the coefficients and the metric tensor.
• Solutions are obtained in two special cases: in one, an additional assumption is made where the matter density and the expansion scalar have a definite relation and in the other a barotropic equation of state between the matter density and the thermodynamic pressure is assumed.
• While the Bianchi II solutions are already found in the literature the other two classes of solutions are apparently new.