There have been attempts to apply renormalization group
techniques, assuming that the transition is indeed continuous.
Burda et al [61] and later Bialas et al [48] considered the ``cutting of the last generation of minimal-neck
baby universes''. This step can only be performed once, which
severely limits the power of the procedure. Renken [178,
177] has applied a different blocking move, involving node deletion,
and studied the RG flow using the volume and the vertex order as
observables.