On Principle of Inertia in Closed Universe
  If our universe is asymptotic to a de Sitter space, it should be closed with curvature in $O(\Lambda)$ in view of dS special relativity. Conversely, its evolution can fix on Beltrami systems of inertia in the dS-space without Einstein's `argument in a circle'. Gravity should be local dS-invariant based on localization of the principle of inertia. 
Han-Ying Guo