Rippled cosmological dark matter from a damped oscillating Newton constant

Abstract

Let the reciprocal Newton ‘constant’ be an apparently non-dynamical Brans–Dicke scalar field damped oscillating towards its general relativistic VEV. We show, without introducing additional matter fields or dust, that the corresponding cosmological evolution averagely resembles, in the Jordan frame, the familiar dark radiation → dark matter → dark energy domination sequence. The fingerprints of our theory are fine ripples, hopefully testable, in the FRW scale factor; they die away at the general relativity limit. The possibility that the Brans–Dicke scalar also serves as the inflaton is favourably examined.