Sounds of a supersolid

At these temperatures, the atoms condense into a single quantum state, a phase of matter known as a Bose-Einstein condensate (BEC). In the standard model of particle physics, symmetry breaking has a key role in the emergence of light particles such as pions, which are responsible for nuclear interactions, and in the Higgs mechanism, which is responsible for much of the mass in the Universe. The nature of these two modes can be understood separately: normal sound in the superfluid is associated with the superfluid flow of the BEC, whereas the supersolid sound mode is associated with oscillation of the crystal structure.