A scalar-tensor bimetric gravity model of early universe cosmology is reviewed .
The metric frame with a variable speed of light ( VSL ) and a constant speed of gravitational waves is used to describe a Friedmann-Robertson-Walker universe .
The Friedmann equations are solved for a radiation dominated equation of state and the power spectrum is predicted to be scale invariant with a scalar mode spectral index n _ { s } = 0.97 .
The scalar modes are born in a ground state superhorizon and the fluctuation modes are causally connected by the VSL mechanism .
The cosmological constant is equated to zero and there is no significant dependence on the scalar field potential energy .
A possible way of distinguishing the bimetric gravity model from standard inflationary models is discussed .