Chen Ning Yang
Name in native script: 杨振宁
1922–2025, Hefei, Anhui, China, Beijing, China
Chinese-American theoretical physicist who co-predicted parity violation with Tsung-Dao Lee and won the 1957 Nobel Prize in Physics.
Born in Hefei, Yang studied at the wartime National Southwestern Associated University before moving to the United States, earning his doctorate at the University of Chicago in 1948. He worked at the Institute for Advanced Study in Princeton from 1949, then moved to Stony Brook University in 1966, where he founded the institute for theoretical physics that now bears his name.
Beyond the Nobel work on parity violation, in 1954 he and Robert Mills constructed the non-Abelian gauge theory — Yang–Mills theory — the mathematical framework that became the foundation of the Standard Model. In 1998 he returned to China, teaching at Tsinghua University, and resumed Chinese citizenship in 2015.
Nobel-winning work
With Tsung-Dao Lee, Yang analyzed the entire body of experimental data of the time and demonstrated that parity conservation had been tested for strong and electromagnetic interactions only — never for weak interactions, although physicists had assumed it universally.
They proposed a battery of decisive tests, including measuring the angular asymmetry of beta decay from polarized nuclei. In January 1957, Chien-Shiung Wu's cobalt-60 experiment confirmed parity violation, and results on muon and pion decay quickly extended it to the whole domain of weak interactions. The discovery overturned a supposedly absolute symmetry law and reshaped particle physics.
Workplaces: Institute for Advanced Study, Stony Brook University, Tsinghua University
United States, China