The quantum solid that defies explanation

Abstract

If a branch of physics were to be judged by the number of Nobel laureates it has produced, then superfluidity would surely rank among the most successful. The field has borne nearly 20 laureates, from the award of the 1913 Nobel Prize for Physics to Heike Kamerlingh Onnes, who discovered superconductivity, to that of the 2003 prize to Alexei Abrikosov, Vitaly Ginzburg and Tony Leggett for their contributions to the theory of superconductors and superfluids. The reason why is simple: these counterintuitive phenomena, whereby below a certain temperature matter flows without resistance, are rare examples of quantum-mechanical behaviour seen at the macroscopic scale.