Thursday, August 6, 2015

Chien Shiung Wu: Madame of the Manhattan Project

Like Lise Meitner, Chien Shing Wu made a fundamental discovery, but her work was overshadowed by her colleagues and snubbed by the Nobel committee.

Early Life

Chien Shing Wu was born on May 31st, 1912 in the town of Liúhé, in the Jiāngsū province of China. In parallel to Lise's childhood, Chien's father -- Wu Zhong-Yi -- encouraged her interests in math and science in an environment where girls were expected to be housewives. Indeed, Wu ran one of China's first schools for girls. Also like Lise, Chien took to teaching as a backup plan in case her scientific aspirations failed, but was not content to abandon her true passion.

In 1930, Chien enrolled at the National Uiversity in Nanjing, at first majoring in math, then physics. From 1931 to 1934, she was politically active, protesting against the Chinese government's lack of action when Japan invaded Manchuria (protesting the Chinese government has historically been a dangerous adventure), but she largely did so because she was pressured to by her fellow students. Chien graduated in 1934 with top honors and did her first research at the Institute of Physics in Shanghai. In Shanghai, Chien conducted X-ray experiments under the mentorship of Jing Wei-gu, a woman who gained her professorship in the United States. However, Chien wanted to pursue graduate level studies, but this was as far as she could go in China.

The Manhattan Project

With the help of her father and backing by Jing, Chien was able to enroll at the University of California at Berkley. There she met Luke Chia Yuan, her future husband. Chien's intellect impressed the faculty, especially professor Emilio Segre and Ernst Lawrence. In 1940, Chien gained her PhD, but universities at the time were reluctant to hire women, so she taught at a woman's college -- Smith College -- and married Luke in 1942. She longed for research and persisted, and got her lucky break from the Manhattan Project.

Chien helped solved the mystery of why the nuclear reactor at Hanford randomly shut down, discovering that certain fission products -- most notably Xenon -- "poisoned" (impeded) the chain reaction by absorbing neutrons. She also contributed to the contributed to the development of the gaseous diffusion process, used to separate Uranium 235 from Uranium 238.

Later Career & Discoveries

Chien's and Luke's son, Vincent Yuan was born in 1947. Chien spent the rest of her career at Columbia University, where she worked on the Manhattan Project. In 1956, she conducted a beta-decay experiment which helped Tsung-Dao Lee and Chen Ning Yang to disproved the hypothetical Law of the Conservation of Parity (that radioactive decay had to produce particles with the same spin as the parent atom). The experiment was a major contribution to the Standard Model, but like Lise Meitner's solving the puzzle of fission, Chien's contributions were ignored.

Chien also contributed to research on Sickle-Cell Anemia, and verified Albert Einstein's "spooky action at a distance" (quantum entanlement). She passed away on Febuary 16th, 1997.

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