Modern low-temperature physics began with the liquefaction of helium by Kamerlingh Onnes (1908) and the discovery of superconductivity (Kamerlingh Onnes, 1911) at the University of Leiden in the early part of the 20th century. There were really two surprises that came out of this early work. One was that essentially all of the electrical resistance of metals like mercury, lead, and tin abruptly...