  A comprehensive transport study, as a function of both temperature and
magnetic field in continuous magnetic fields up to 45 T reveals that URu2Si2
possesses all the essential hallmarks of quantum criticality at temperatures
above 5.5 K and fields around 38 T, but then collapses into multiple low
temperature phases in a hierarchically-organized phase diagram as the
temperature is reduced. Although certain generic features of the phase diagram
are very similar to those in the cuprates and heavy fermion superconductors,
the existence of multiple ordered hysteretic phases near the field-tuned
quantum critical point is presently unique to URu2Si2. This finding suggests
the existence of many competing order parameters separated by small energy
difference in URu2Si2.
