Primordial perturbations generated by Higgs field and R2 operator

If the very early Universe is dominated by the nonminimally coupled Higgs field and Starobinsky’s curvature-squared term together, the potential diagram would mimic the landscape of a valley, serving as a cosmological attractor. The inflationary dynamics along this valley is studied, model parameters are constrained against observational data, and the effect of isocurvature perturbation is estimated.