Physicists built a perfect conductor from ultracold atoms

Researchers at TU Wien have discovered a quantum system where energy and mass move with perfect efficiency. In an ultracold gas of atoms confined to a single line, countless collisions occur—but nothing slows down. Instead of diffusing like heat in metal, motion travels cleanly and undiminished, much like a Newton’s cradle. The finding reveals a striking form of transport that breaks the usual rules of resistance.