Cosmic acceleration and $f(R)$ theory: perturbed solution in a matter FLRW model

Understand

In the present paper we consider $f(R)$ gravity theories in the metric approach and we derive the equations of motion, focusing also on the boundary conditions.

• In such a way we apply the general equations to a first order perturbation expansion of the Lagrangian.
• We present a model able to fit supernovae data without introducing dark energy.