Three distinct time crystals found in the same experiment?

Time crystals — matter that oscillates forever without energy input — are notoriously hard to distinguish from one another. Using atoms trapped inside an optical cavity, researchers show how three fundamentally different time-crystalline phases arise in the same platform and can be told apart through photon emission patterns and atomic momentum snapshots. The cavity's real-time light readout sidesteps the usual destructive measurements that plagued cold-atom experiments, offering a practical blueprint for studying exotic dynamical phases.