The Big Bang should have created equal amounts of matter and antimatter, but there is far more matter in the universe, and one of the keys to explaining why is finding a difference in how matter and antimatter behave, known as charge–parity violation.

Using the Large Hadron Collider at CERN, Xueting Yang and colleagues of the LHCb experiment have seen this difference for the first time in a type of subatomic particle called a baryon. Baryon particles include neutrons and protons and make up most of the matter we can observe in the Universe.

While such a violation was predicted and does not resolve the Big Bang matter–antimatter imbalance, finding out the details of this violation experimentally will offer important clues, opening up opportunities for further theoretical and experimental studies of the nature of CP violation.