A lattice bosonic model as a quantum theory of gravity
  A local quantum bosonic model on a lattice is constructed whose low energy excitations are gravitons described by linearized Einstein action. Thus the bosonic model is a quantum theory of gravity, at least at the linear level. We find that the compactification and the discretization of metric tenor are crucial in obtaining a quantum theory of gravity. 
Zheng-Cheng Gu and Xiao-Gang Wen