Events

Superfluidity - the ability of liquid 4He, when cooled below 2.176 K, to flow without resistance through narrow pores - is one of the most amazing phenomena in physics. Supersolidity - the coexistence of superfluid behavior with the crystalline order of a solid - was proposed theoretically long ago as an even more exotic phase of solid 4He, but it has eluded detection until recently. In 2004, Kim and Chan (E. Kim and M. H. W. Chan, Nature (London) 427, 225 (2004); E. Kim and M. H. W.