Abstract
Abstract
Within the framework of metric-affine theories of gravity, where both the metric and
connection are treated as independent variables, we consider actions quadratic in the Ricci scalar
curvature coupled non-minimally to a scalar field through derivative couplings. Our analysis
delves into the inflationary predictions, revealing their consistency with the latest
observational constraints across a wide range of parameters. This compatibility permits
adjustments such as an increase in the spectral index and a reduction in the tensor-to-scalar
ratio. While we do not propose a specific reheating mechanism, our analysis demonstrates that
within the quadratic model of inflation, the maximum reheating temperature can reach ∼
3 × 1015 GeV.