“…Strongly correlated electron systems exhibit quantum criticality [24][25][26], which is essentially a T = 0 phenomenon. An exciting direction is the extension of studies of quantum criticality to lower temperature, for example to understand the role of nuclear magnetism, particularly in systems with strong hyperfine interactions [27][28][29][30]. Cooling to below 1 mK allows access to magnetic field-to-temperature ratios, B/T , unachievable elsewhere.…”