We propose that large quantum fluctuations of the conformal factor dra
stically modify classical general relativity at cosmological distance
scales, resulting in a scale invariant phase of quantum gravity in the
far infrared. We derive scaling relations for the partition function
and physical observables in this conformal phase, and suggest quantita
tive tests of these relations in numerical simulations of simplicial f
our geometries with S4 topology. In particular, we predict the form of
the critical curve in the coupling constant plane, and determine the
scaling of the Newtonian coupling with volume which permits a sensible
continuum limit. The existing numerical results already provide some
evidence of this infrared fixed point and new conformal invariant phas
e of quantum gravity.