Cooled to a billionth of a degree, atoms stop acting like individuals

In 1995, Eric Cornell and Carl Wieman cooled a cloud of rubidium atoms to within a few billionths of a degree of absolute zero — cold enough that thousands of atoms collapsed into a single quantum state predicted by Einstein and Bose 70 years earlier. The result, a Bose-Einstein condensate, behaves as one giant 'super-atom' rather than separate particles.

— Mike Anderson, Eric Cornell, Carl Wieman et al., Observation of Bose-Einstein Condensation in a Dilute Atomic Vapor — Science, 1995