Can hyperbolic phase of Brans - Dicke field account for Dark Matter?

Abstract

We show that the introduction of a hyperbolic phase of the Brans-Dicke (BD) field results in a flat vacuum cosmological solution of the Hubble parameter H and a fractional rate of change of the BD scalar field F, which asymptotically approach constant values. At later stages, the hyperbolic phase of the BD field behaves like dark matter.