Subject: biography, physics
Chinese-born US physicist, teacher, and researcher in nuclear physics. Her work changed the accepted view of the structure of the universe. She was the first woman to receive an honorary doctorate of science from Princeton University, New Jersey, the first woman elected president of the American Physical Society, and the first woman awarded the Wolf Prize from the state of Israel. She was also the first living scientist to have an asteroid named after her.
Born in Liu-ho, Kiangsu Province, on 31 May 1912, Wu received a BSc from the National Central University in 1934. She moved to the USA in 1936 to work under US physicist Ernest O Lawrence at the University of California at Berkeley, gaining a PhD in 1940. She spent a short time teaching at Smith College, Northampton, Massachusetts, and then took up a post at Princeton University. In 1944 she worked on radiation detection in the division of war research at Columbia University,becoming a staff member in 1946. She spent the rest of her career there, becoming professor of physics in 1957. In 1972 she became the Pupin Professor of Physics at Columbia.
In the 1950s Wu's research focused on the mechanism of beta disintegration in radioactive decay. She demonstrated in 1956 that the direction of the emission of beta rays is strongly correlated with the direction of spin of the emitting nucleus. Her experiment, performed by cooling cobalt-60 in a magnetic field so that the their spins were aligned, confirmed the hypotheses of Chinese physicists Yang Chen Ning and Lee Tsung Dao (see Yang and Lee) that the 'law of symmetry' was violated in 'weak' nuclear interactions. Yang and Lee received the Nobel Prize in 1957 for their theory, which overturned many of the central tenets of physics. In 1958 Wu experimentally confirmed US physicists Richard Feynman and Murray Gell-Mann's theory of conservation of vector current in beta decay.
Wu made many contributions to elementary particle physics including demonstrating that the electromagnetic radiation from the annihilation of positrons and electron is polarized, proving that electrons and positrons have opposite parity, as predicted by Paul Dirac's theory of the electron. In recognition of her contributions to atomic research and the understanding of beta decay and weak interactions, she was awarded the Research Corporation Award and the Comstock Prize from the National Academy of Sciences. Wu also undertook studies of the X-ray spectra of muonic atoms and in her later years became interested in the structure of haemoglobin. She retired from Columbia in 1981.