The Countable Number of Models in the Cosmology with Nonminimal Coupling and Torsion

Cosmological models of flat space with a nonminimally coupled scalar field and ultrarelativistic gas are studied within the Einstein–Kartan theory. Exact general solutions are derived for two-component models and those containing only scalar field for an arbitrary coupling constant ξ. It is shown that both singular and countable number of nonsingular models is possible depending on the type of scalar field and the sign of ξ. The special values of ξ and restrictions on ξ are found for the above solutions. The role of relativistic gas in the evolution of models is revealed.