  We study the collapse in spherical symmetry of a massless scalar field
minimally coupled to gravity using the semiclassical equations that are
expected from loop quantum gravity. We find critical behavior of the mass as a
function of the parameters of the initial data similar to that found by
Choptuik in classical general relativity for a large set of initial data and
values of the polymerization parameter. Contrary to wide expectations for
quantum gravity, our semiclassical field equations have an exact scale
invariance, as do the classical field equations. As one would then expect, we
numerically find that the phase transition is second order, again as in the
classical case.
