Cosmological implications of hybrid metric-Palatini $f(\mathcal{R},{\mathcal{R}}_{\mu \nu }{\mathcal{R}}^{\mu \nu })$ gravity

Shahab Shahidi, Shiva Kayedi

The hybrid metric-Palatini gravity with Lagrangian density $L=R+f(\mathcal{R},{\mathcal{R}}_{\mu \nu }{\mathcal{R}}^{\mu \nu })$ is considered, where $R$ is the metric Ricci scalar and $\mathcal{…