Discovering new phases of matter and classifying such phases are among the most important goals in physics. In a new study, Dr Tie-Cheng Guo and Professor Li You at Tsinghua University in Beijing present a new methodology to discover new quantum phases of matter, using the concept of ‘time order’. Through identifying and defining quantum phases from this perspective, time order could become a new paradigm in physics, helping researchers to gain more insight into quantum many-body systems.