Showing papers by "Salvatore Capozziello published in 1991"
01 Jan 1991
TL;DR: In this paper, the curvature squared term of the Friedmann-Robertson-Walker metric with scale factor a(t) has been used to model the trajectories of cosmological models projected onto a 2D phase space.
Abstract: Generalized theories of gravity can be viewed in a unified way when the trajectories of cosmological models can be projected onto a two dimensional phase space. This tool is applied here to the case of a non-minimally coupled scalar field, to the compactification of multidimensional cosmology, and to fourth order gravity. In conclusion, as a natural follow-up of these models, we outline the possibility of a scalar coupling with the curvature squared term. In all cases, we have in mind a spatially flat Friedmann-Robertson-Walker metric with scale factor a(t).