Cosmological dynamics in six-order gravity

Understand

We consider cosmological dynamics in generalized modified gravity theory with the $R\Box R$ term added to the action of the form $R+R^N$.

• Influence of $R \Box R$ term to the known solutions of modified gravity is described.
• We show that in particular case of $N=3$ these two non-Einstein terms are equally important on power-law solutions.
• These solutions and their stability have been studied using dynamical system approach.