Generation of exact solutions in cosmology on the basis of five-dimensional Projective Unified Field Theory

Abstract

A homogeneous and isotropic model of the Universe is considered in the framework of the five-dimensional Projective Unified Field Theory in which the gravitation is described by both space-time curvature and some hypothetical scalar field (sigma-field). We propose a generation method for obtaining exact solutions. New exact Friedmann-like solutions for a dust model and inflationary solutions are found. It is shown that in the framework of exponential type inflation we obtain a natural explanation of why at present we do not observe sigma-field effects or why these effects are negligible.