FRW MODELS WITH PERFECT FLUID AND SCALAR FIELD IN HIGHER DERIVATIVE THEORY.

In this paper we study the dynamics of the universe in Friedmann-Robertson-Walker models including perfect fluid and coupled scalar field with nonzero scalar potential in higher derivative theory of gravitation. We study the evolution of the universe by assuming the scalar potential and scale factor as functions of the scalar field. Exact cosmological solutions are obtained for flat, closed and open models, which are physically interesting for the description of the present-day universe. The properties of scalar field and other physical parameters are discussed in detail. Some special cases have been studied by imposing certain constraints on constants to discuss the decelerated and accelerated phases of the universe. [ABSTRACT FROM AUTHOR]