General Relativity As an Attractor to Scalar-Tensor Gravity Theories

Abstract

We investigate the conditions under which general scalar-tensor gravity theories relax towards General Relativity. We extend the work of Damour and Nordtvedt [2] by studying the effects of the inclusion of a cosmological potential term. When the universe is either radiation dominated or vacuum, we find that Einstein’s gravity is indeed a cosmological attractor and, also, that the universe exhibits inflationary expansion. This latter feature provides another striking argument in favour of the inflationary paradigm, which in the present setting arises without the intervention of the usual inflaton field.