The initial fate of an anisotropic JBD universe

The dynamical effects on the scale factors due to the scalar phi-field at t he early stages of a supposedly anisotropic Universe expansion in the scala r-tensor cosmology of Jordan, Brans and Dicke is studied. This universe sho ws an isotropic evolution and, depending on the value of the theorie's coup ling parameter omega, it can begin from a singularity if omega > 0 and afte r expanding shrink to another one; or, if omega < 0 and -3/2 < omega less t han or equal to - 4/3, it can evolve from a flat spatially-infinite state t o a non extended singularity; or, if -4/3 < omega < 0, evolve from an exten ded singularity to a non singular state and, at last, proceed towards a sin gularity. (C) 1999 Published by Elsevier Science B.V. All rights reserved.