With the help of Nordtvedt's scalar tensor theory an exact analytical model of a non-minimally coupled scalar field cosmology in which the gravitational coupling $G$ and the Hubble factor $H$ oscillate during the radiation era is presented. A key feature is that the oscillations are confined to the early stages of the radiation dominated era with $G$ approaching its present constant value while $H$ becoming a monotonically decreasing function of time. The Brans Dicke parameter $\omega$ is chosen to be a function of Brans Dicke scalar field so that no conflict with observational constraints regarding its present value arises.
Categories: gr-qc astro-ph hep-ph