Shi-Xin Zhang

In 1963, a Tanzanian schoolboy named Erasto Mpemba noticed that hot ice cream freezes faster than cold. That paradox, named after him, long remained a subject of debate in classical thermodynamics. Now the quantum world offers its own version: a state with more strongly broken symmetry can recover it faster than a less broken one.

A quantum computer relies on two forces: entanglement (particles behaving as a single whole) and "magic"—a measure of how far a state is from familiar classical physics. But how these two resources relate as a many-particle system evolves in time has remained a puzzle. The authors approached the problem through time.