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Cylindrically symmetric viscous fluid universe in Lyra geometry. (English) Zbl 1202.83029
A new class of cylindrically symmetric homogeneous cosmological models for viscous fluid distribution is obtained in the context of Lyra’s geometry. We have obtained solutions by considering the time dependent displacement field. To get the deterministic solutions of Einstein’s modified field equations, the free gravitational field is assumed to be of type D which is of the next order in the hierarchy of Petrov classification. It has been found that the displacement vector $\beta(t)$ behaves like cosmological term $\Lambda$ in the normal gauge treatment and the solutions are consistent with the observations. The displacement vector $\beta(t)$ affects entropy. Some physical and geometrical properties of the models are discussed. Editorial remark: No review copy delivered.

##### MSC:
 83C20 Classes of solutions of equations in general relativity 83C15 Closed form solutions of equations in general relativity
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