1303.4330 (A. Avilez et al.)

Cosmological constraints on Brans-Dicke theory    [PDF]

A. Avilez, C. Skordis

We report strong cosmological constraints on the Brans-Dicke theory of gravity using Cosmic Microwave Background data. We consider two types of models. First, the initial condition of the scalar field is fixed to give the same effective gravitational strength G_{eff} today as the one measured on the Earth, G_N. In this case the BD parameter \omega is constrained to \omega> 177 at the 95% confidence level, improving by a factor of two over previous constraints. In the second type the initial condition for the scalar is a free parameter leading to a somewhat stronger constrain of \omega > 288 while G_{eff} is constrained to 0.97View original: http://arxiv.org/abs/1303.4330