Scalar gravity and higgs mechanism

The role that the auxiliary scalar field phi plays in Brans-Dicke cosmology is discussed. If a constant vacuum energy is assumed to be the origin of dark energy, then the corresponding density parameter would be a quantity varying with phi; and almost all of the fundamental components of our universe can be unified into the dynamical equation for phi. As a generalization of Brans-Dicke theory, we propose a new gravity theory with a complex scalar field phi which is coupled to the cosmological curvature scalar. Through such a coupling, the Higgs mechanism is naturally incorporated into the evolution of the universe, and a running density of the field vacuum energy is obtained which may release the particle standard model from the rigorous cosmological constant problem in some sense. Our model predicts a running mass scale of the fundamental particles in which the gauge symmetry breaks spontaneously. The running speed of the mass scale in our case could survive all existing experiments