Chien-Shiung Wu, 84; Physicist Worked on Manhattan Project

Chien-Shiung Wu, a physicist who worked on the Manhattan Project and later conducted a landmark experiment in physics, is dead at 84.

Wu died of a stroke Sunday, according to Columbia University, where she had taught for more than three decades.

Born in Shanghai, Wu came to the United States in 1936 and received her doctorate in physics from UC Berkeley. She went on to teach at Smith College and Princeton University.

In the 1940s, Wu worked on the Manhattan Project, a covert program to build an atomic bomb in World War II. She joined Columbia after the war.

She is best known for her 1956 experiment that disproved the so-called “conservation of parity,” or symmetry of the right and left sides in nature.

Wu studied how cobalt emitted electrons and discovered that the movement was not symmetrical. Her book, “Beta Decay,” remains the standard reference text on low-energy emission of electrons by decaying atoms.

In 1973, she became the first woman to head the American Physical Society.

She was “one of the giants of physics,” said Professor Tsung-Dao Lee of Columbia, from which Wu retired in 1980.