I. Ayuso, J. P. Mimoso, N. J. Nunes
In this work, we seek a cosmological mechanism that may define the sign of the effective gravitational coupling constant, G. To this end, we consider general scalar-tensor gravity theories as they provide the field theory natural framework for the variation of the gravitational coupling. We find that models with a quadratic potential naturally stabilize the value of G into the positive branch of the evolution and further, that de Sitter inflation and a relaxation to General Relativity is easily attained.
gravitation; modified gravity; cosmology; variation of constants
Volume 7, Number 1, Page 38