Cosmological Evolution of Two-Scalar fields Cosmology in the Jordan frame

Understand

In the present article we study the cosmological evolution of a two-scalar field gravitational theory defined in the Jordan frame.

• Specifically, we assume one of the scalar fields to be minimally coupled to gravity, while the second field which is the Brans-Dicke scalar field is nonminimally coupled to gravity and also coupled to the other scalar field.
• In the Einstein frame this theory reduces to a two-scalar field theory where the two fields can interact only in the potential term, which means that the quintom theory is recovered.
• The cosmological evolution is studied by analyzing the equilibrium points of the field equations in the Jordan frame.