A research team has observed multibody interaction-induced EPs and hysteresis trajectories in cold Rydberg atomic gases. They revealed the phenomenon of charge-conjugation parity (CP) symmetry breaking in non-Hermitian multibody physics.

The team was led by Prof. Guo Guangcan, Prof. Shi Baosen and Prof. Ding Dongsheng from the University of Science and Technology of China (USTC) of the Chinese Academy of Sciences, and their study was published in Nature Communications.

CP-symmetry is an important discrete symmetry in particle physics. When certain physical processes exhibit asymmetry under CP transformation, it is referred to as the breaking of CP-symmetry, such as in the decay of neutral K mesons (K⁰) and B meson decay.