Analysis of the Wheeler-DeWitt Equation beyond Planck Scale and   Dimensional Reduction
  We solve the Wheeler-DeWitt equation for {\it four}-dimensional Einstein gravity as an expansion in powers of the Planck mass by means of a heat kernel regularization. Our results suggest that in the universe with a very small radius or with a very large curvature beyond a Planck scale expectation values of operators are reduced to calculations in a path integral representation of {\it three}-dimensional Einstein gravity. 
T.Horiguchi, K.Maeda and M.Sakmaoto