Towards a sound massive cosmology
  It is known that de Rham-Gabadadze-Tolley (dRGT) massive gravity does not
permit a homogeneous and isotropic universe with flat or spherical spatial
metrics. We demonstrate that a singular reference metric solves this problem in
an economic and straightforward way. In the dRGT massive gravity with a
singular reference metric, there are sound homogeneous and isotropic
cosmological solutions. We investigate cosmologies with the static and
dynamical singular reference metrics, respectively. The term like dark energy
appears naturally and the universe accelerates itself in some late time
evolution. The term simulating dark matter also naturally emerges. We make a
preliminary constraint on the parameters in the dRGT massive gravity in frame
of the present cosmological model by using the data of supernovae, cosmic
microwave back ground radiations, and baryonic acoustic oscillations.
