A Superfluid Universe Quotes

“Landau [3] proposed a general phenomenological theory of phase transitions, based on the idea that the system changes from a less “ordered” state to a more ordered one, or vice versa. The precise meaning of “order” depends on the system, but the general idea of a change in order applies to all. One can quantify the amount of order present by an “order parameter”, which is a complex field in the case of Bose–Einstein condensation, because the “order” pertains to a phase angle.”
― Kerson Huang, Superfluid Universe, A

“3He becomes a superfluid below 10−3 K, when its fermionic atoms pair up into bosons and condense. Similar condensation of paired fermions also occurs in neutron stars at about 106 K.”
― Kerson Huang, Superfluid Universe, A