String cosmological models with bulk viscosity in Nordtvedt s general scalar-tensor theory of gravitation

We have obtained and presented spatially homogeneous Bianchi types II, VIII, and IX string cosmological modelswith bulk viscosity in Nordtvedt s (Astrophys. J. 161:1059, 1970) general scalar-tensor theory of gravitation with thehelp of a special case proposed by Schwinger. It is observed that only the bulk viscous cosmological model existsin the case of Bianchi type IX universe. Some important features of the models, thus obtained, have been discussed.

Keywords:

Bulk viscosity , Cosmic strings , Bianchi type II , VIII , and IX metrics , Nordtvedt s general scalar-tensor theory