Dynamical analysis for a scalar-tensor model with Gauss-Bonnet and non-minimal couplings

Understand

We study the autonomous system for a scalar-tensor model of dark energy with Gauss-Bonnet and non-minimal couplings.

• The critical points describe important stable asymptotic scenarios including quintessence, phantom and de Sitter attractor solutions.
• Two functional forms for the coupling functions and the scalar potential were considered: power-law and exponential functions of the scalar field.
• For the exponential functions the existence of stable quintessence, phantom or de Sitter solutions, allows an asymptotic behavior where the effective Newtonian coupling becomes constant.