A second-order phase transition in CDT
  Causal Dynamical Triangulations (CDT) are a concrete attempt to define a nonperturbative path integral for quantum gravity. We present strong evidence that the lattice theory has a second-order phase transition line, which can potentially be used to define a continuum limit in the conventional sense of nongravitational lattice theories. 
J. Ambjorn, S. Jordan, J. Jurkiewicz, R. Loll
hep-th gr-qc hep-lat