Quasi-dilaton non-linear massive gravity: Investigations of background cosmological dynamics

We investigate cosmological behavior in the quasi-Dilaton non-linear massive gravity. We perform a detailed dynamical analysis and examine the stable late-time solutions relevant to late time cosmic acceleration. We demonstrate that a dark-energy dominated, cosmological-constant-like solution is a late attractor of the dynamics. We also analyze the evolution of the universe at intermediate times, showing that the observed epoch sequence can be easily obtained in the model under consideration. Furthermore, we study the non-singular bounce and the cosmological turnaround which can be realized for a region of the parameter space. Last but not least, we use observational data from Type Ia Supernovae (SNIa), Baryon Acoustic Oscillations (BAO) and Cosmic Microwave Background (CMB), in order to constrain the parameters of the theory.