Chen-ning Yang

Biography

Yang Chen-ning, also known as C.N. Yang or Franklin Yang, was a Chinese-American theoretical physicist whose work changed the understanding of particle physics and symmetry laws. Born on October 1, 1922, in Hefei, China, Yang became one of the most influential physicists of the 20th century through his groundbreaking work in statistical mechanics, gauge theory, and particle physics. His most famous achievement came in 1957 when he and Tsung-Dao Lee won the Nobel Prize in Physics for showing parity violation in weak nuclear interactions, challenging a long-held belief about the symmetry of physical laws.

Yang's education took him through China's top schools and leading American universities. He studied at the National Southwestern Associated University, Tsinghua University, and Peking University before finishing his graduate studies at the University of Chicago, where he laid the theoretical groundwork for his career. His work with Robert Mills in 1954 led to the Yang-Mills theory, a critical part of the Standard Model of particle physics that explains the forces within atomic nuclei.

The collaboration between Yang and Tsung-Dao Lee was one of the most successful in modern physics. Their idea that parity conservation, previously thought to be a universal law, could be broken in weak nuclear reactions was confirmed by Chien-Shiung Wu's experiment in 1956. This discovery not only earned them the Nobel Prize but also opened new research paths in particle physics and cosmology, affecting generations of physicists and deepening the understanding of fundamental asymmetries in nature.

Throughout his career, Yang worked at top institutions and received many honors beyond the Nobel Prize, such as the Benjamin Franklin Medal, the Rumford Prize, the National Medal of Science, and the Josiah Willard Gibbs Lectureship. He was a Fellow of both the American Physical Society and the American Association for the Advancement of Science and received honorary doctorates from the Chinese University of Hong Kong and Fudan University. In his personal life, Yang was married to Du Zhili and later to Weng Fan, and he kept close ties with both Chinese and American academic communities during his long career. He passed away on October 18, 2025, in Beijing, and his scientific contributions continue to impact theoretical physics research around the world.