Warming Up to Criticality: Quantum change, one bubble at a time

Physicists have had their first look at how matter transitions into an exotic state known as a Bose-Einstein condensate—an ultracold fluid that displays quantum behavior.

BUBBLING QUANTUM STATES. Two streams of atoms drop from slices of a cloud of rubidium into a detector. If the atoms come from the same Bose-Einstein bubble, they’ll share a quantum state and show wavelike interference.