Dynamical stability of Minkowski space in higher order gravity

Understand

We discuss the Minkowski stability problem in modified gravity by using dynamical system approach.

• The method to investigate dynamical stability of Minkowski space was proposed.
• This method was applied for some modified gravity theories, such as $f(R)$ gravity, $f(R)+\alpha R\Box R$ gravity and scalar-tensor gravity models with non-minimal kinetic coupling.
• It was shown that in the case of $f(R)$ gravity Minkowski solution asymptotically stable in ghost-free ($f'>0$) and tachyon-free ($f">0$) theories in expanding Universe with respect to isotropic and basic anisotropic perturbations.