Chien-Shiung Wu in 1963 at Columbia University
Chien-Shiung Wu in 1958 at Columbia University
(simplified Chinese: ; traditional Chinese: ; pinyin: Wú Jiànxíong, May 31, 1912 – February 16, 1997) was a Chinese–American physicist with expertise in the techniques of experimental physics and radioactivity. Wu worked on the Manhattan Project (she helped to develop the process for separating uranium metal into the U-235 and U-238 isotopes by gaseous diffusion). She later performed experiments that contradicted the “Law of Conservation of Parity” and which confirmed the theories of colleagues. Her honorary nicknames include the “First Lady of Physics”, the “Chinese Marie Curie“, and “Madame Wu”.
Life in China
Wu was born on May 31, 1912, in her ancestral hometown in Taicang, Jiangsu Province, China. Wu was the only child. She was raised in Liuhe, a small town in Taicang about 40 miles from Shanghai. Her father, Wu Zhongyi (), was a proponent of gender equality, and he founded the Mingde Women’s Vocational Continuing School. Wu left her hometown at the age of 11 to go to the Suzhou Women’s Normal School No. 2.
In 1929 Wu was admitted to the National Central University which later became the Nanjing University in mainland China and was reinstated in Taiwan. According to the governmental regulations of the time, “normal school” (teacher-training college) students wanting to move on to the universities needed to serve as schoolteachers for one year. Hence, in 1929 Wu went to teach in the Public School of China (W), which had been founded by Hu Shi in Shanghai.
From 1930 to 1934, Wu studied in the Physics Department of the National Central University. For two years after graduation, she did graduate-level study in physics and also worked as an assistant at the Zhejiang University. After this, Wu became a researcher at the Institute of Physics of the Academia Sinica.
edit] Life in the United States of America
Wu decided that she wanted to and needed to continue her studies in physics to a higher level than was possible to do in China. Therefore, she started making applications to study at universities overseas, especially in California. Upon receiving a favorable response in 1936, Wu and her female friend, Dong Ruofen (), a chemist from Taicang, China, embarked on the long steamship voyage from China to the West Coast of the United States.
The two women most likely arrived at the large seaport of San Francisco, because Wu enrolled in graduate school at the University of California located then just in Berkeley, California, which is also on San Francisco Bay. After some time there, Wu’s high abilities and good fortune found her a position as a graduate student under the supervision of one of the world’s leading physicists, Ernest O. LawrenceHYPERLINK “http://www.columbia.edu/cu/record/archives/vol22/vol22_iss15/record2215.16.html”, who won the Nobel Prize for Physics in 1939 for his invention of the cyclotron particle accelerator and the development of its applications in physics.
Under Dr. Lawrence, Wu made rapid progress in her education and her research, and she completed her Ph.D. degree in 1940.
Wu married the physicist Luke Chia-Liu Yuan(), two years later, in 1942. Luke Chia-Liu Yuan’s grandfather was Yuan Shikai, the first President of the Republic of China and in his final days—notoriously—a short-lived, self-proclaimed Emperor of China. Wu and her husband became the parents of one son, Vincent Yuan (), who also became a physicist.
Wu died on February 16, 1997 after suffering her second stroke at the age of 84.
The new Yuan family moved to the East Coast of the U.S., where Wu became a faculty member at, first, Smith College, then Princeton University in New Jersey for 1942－44, and finally at Columbia University in New York City, beginning in 1944 and continuing for many years after the war, all the way through 1980.
At Columbia University, Wu also did research and development for the Manhattan Project. She helped to develop the process for separating uranium metal into the U-235 and U-238 isotopes by gaseous diffusion. This was the process that was implemented on a gigantic scale at the K-25 Plant near Oak Ridge, Tennessee, whose construction began in 1944.
At Columbia Wu knew the Chinese-born theoretical physicist Tsung-Dao Lee personally. In the mid-1950s, Lee and another Chinese theoretical physicist, Chen Ning Yang, grew to question a hypothetical law in elementary particle physics, the “Law of Conservation of Parity“. Their library research into experimental results convinced them that this “Law” was valid for electromagnetic interactions and for the strong nuclear force. However, this “Law” had not been tested for the weak nuclear force, and Lee & Yang’s theoretical studies showed that was probably not true. Lee and Yang worked out the pencil and paper design of several experiments for testing the “Conservation of Parity” in the laboratory. Lee then turned to Wu for her expertise in choosing and then working out the hardware manufacture, set-up, and laboratory procedures for carrying out the experiment.
Wu chose to do this for an experiment that involved taking a sample of radioactive cobalt 60 and cooling to cryogenic temperatures with liquid gasses. Cobalt 60 is an isotope that decays by beta particle emission, and Dr. Wu was also an expert on beta decay. The extremely low temperatures were needed to reduce the amount of thermal vibration of the cobalt atoms to practically nil. Also, Dr. Wu needed to apply a constant and uniform magnetic field across the sample of cobalt 60 in order to cause the spin axes of the atomic nuclei to all line up in the same direction.
For this cryogenic work, Dr. Wu needed the expertise and the facilities of the National Bureau of Standards in liquid gases to aid her. She thus traveled to NBS headquarters in Maryland with her equipment to carry out the experiments.
Lee and Yang’s theoretical calculations predicted that the beta particles from the cobalt 60 atoms would be emitted asymmetrically if the hypothetical “Law of Conservation of Parity” proved invalid. Dr. Wu’s experiments at the NBS showed that this is indeed the case: parity is not conserved under the weak nuclear interactions. This was also very soon confirmed by her colleagues at Columbia University in different experiments, and as soon as all of these results were published—in two different research papers in the same issue of the same physics journal—the results were also confirmed at many other laboratories and in many different experiments.
The discovery parity violation was a major contribution to high energy physics and the development of the Standard model. In recognition for their theoretical work, Lee and Yang were awarded the Nobel Prize for Physics in 1957. Wu received the first Wolf Prize in Physics in 1978 for her experimental work.
An additional important experiment carried out by Dr. Wu was the confirmation of the Pryce and Ward calculations on the correlation of the quantum polarizations of two photons propagating in opposite directions. This was the first experimental confirmation of quantum results relevant to a pair of entangled photons as applicable to the Einstein-Podolsky-Rosen (EPR) paradox, or situation.
 Other work and accomplishments
Wu’s book titled Beta Decay (published 1965) is still a standard reference for nuclear physicists.
Wu’s career presented a number of breakthroughs.
- Wu is believed to be the only Chinese person to have taken part in the Manhattan Project.
She also was the first:
- Chinese-American to be elected into the U.S. National Academy of Sciences;
- Female instructor in the Physics Department of Princeton University;
- Woman with an honorary doctorate from Princeton University;
- Female President of the American Physical Society, elected in 1975;
- Person selected to receive the Wolf Prize in Physics in its inaugural year of 1978.
Wu was one of the first Chinese-American educators to travel to Red China for visits in the 1970s. She also was the first living scientist to have an asteroid named after her.
Tsung-Dao (T.D.) Lee, a student of Enrico Fermi
Tsung-Dao Lee (T.D. Lee, Chinese: 李政道; pinyin: Lǐ Zhèngdào) (born November 24, 1926) is a Chinese-born American physicist, well known for his work on parity violation, the Lee Model, particle physics, relativistic heavy ion (RHIC) physics, nontopological solitons and soliton stars. He holds the rank of University Professor at Columbia University, where he has taught since 1953 and from which he will retire in 2012.
Lee is the youngest Nobel laureate after World War II, and the third youngest in history after W. L. Bragg (who won the prize at 25 with his father W. H. Bragg in 1915) and Werner Heisenberg (who won in 1932 also at 30). Lee and Yang were the first Chinese laureates. Since naturalized as American citizen in 1962, Lee thus is also the youngest American who has ever won a Nobel Prize.
Lee’s father Chun-kang Lee (simplified Chinese: 李骏康; traditional Chinese: 李駿康; pinyin: Lǐ Jùn-kāng), one of the first graduates of the University of Nanking, was a chemical industrialist and merchant who was involved in China’s early development of modern synthesized fertilizer. Lee’s grandfather Chong-tan Lee (Chinese: 李仲覃; pinyin: Lǐ Zhòng-tán) was the first Chinese Catholic rector in Suzhou whose residence was the famous St. John’s Church in Suzhou (蘇州聖約翰堂).
Lee has four brothers and one sister. Educator Robert C.T. Lee is one of T. D.’s brothers. Lee’s mother Chang and brother Robert C. T. moved to Taiwan. They were accidentally jailed when the Communists tried to send spies in Taiwan.
Lee received his secondary education in Shanghai and Jiangxi. Due to the Second Sino-Japanese war, Lee’s high school education was interrupted, thus he did not obtain his secondary diploma. Nevertheless, in 1943, Lee directly applied and was admitted by the National Chekiang University (now Zhejiang University). Initially, Lee registered as a student in the Department of Chemical Engineering. Very quickly, Lee’s talent was discovered and his interest in physics grew rapidly. Several physics professors, including Shu Xingbei and Kan-Chang Wang, largely guided Lee, and he soon transferred into the Department of Physics of Zhejiang University, where he studied in 1943–1944.
However, again disrupted by a further Japanese invasion, Lee continued at the National Southwestern Associated University (國立西南聯合大學) in Kunming the next year in 1945, where he studied with Professor Ta-You Wu.
research in USA
Professor Wu nominated Lee for a Chinese government fellowship for graduate study in USA. In 1946, Lee went to the University of Chicago and was selected by Professor Enrico Fermi to become his PhD student. Lee completed his PhD thesis under Fermi in 1950. Lee served as research associate and lecturer in physics at the University of California at Berkeley from 1950 to 1951.
In 1953, Lee joined Columbia University, where he remains today. His first work at Columbia was on a solvable model of quantum field theory better known as the Lee Model. Soon, his focus turned to particle physics and the developing puzzle of K meson decays. Lee realized in early 1956 that the key to the puzzle was parity non-conservation. At Lee’s suggestion, the first experimental test was on hyperion decay by the Steinberger group. At that time, the experimental result gave only an indication of a 2 standard deviation effect of possible parity violation. Encouraged by this feasibility study, Lee made a systematic study of possible P,T,C and CP violations in weak interactions with collaborators, including C. N. Yang. After the definitive experimental confirmation by C.S . Wu and her collaborators of parity non-conservation, Lee and Yang were awarded the 1957 Nobel Prize for Physics.
In the early 1960s, Lee and collaborators initiated the important field of high energy neutrino physics. In 1964, Lee, with M. Nauenberg, analyzed the divergences connected with particles of zero rest mass, and described a general method known as the KLN theorem for dealing with these divergences, which still plays an important role in contemporary work in QCD, with its massless, self-interacting gluons. In 1974–75, Lee published several papers on “A New Form of Matter in High Density”, which led to the modern field of RHIC physics, now dominating the entire high energy nuclear physics field.
Besides particle physics, Lee has been active in statistical mechanics, astrophysics, hydrodynamics, many body system, solid state, lattice QCD. In 1983, Lee wrote a paper entitled, “Can Time Be a Discrete Dynamical Variable?”; which led to a series of publications by Lee and collaborators on the formulation of fundamental physics in terms of difference equations, but with exact invariance under continuous groups of translational and rotational transformations. Beginning in 1975, Lee and collaborators established the field of non-topological solitons, which led to his work on soliton stars and black holes throughout the 1980s and 1990s.
From 1997 to 2003 Lee was director of the RIKEN-BNL Research Center (now director emeritus), which together with other researchers from Columbia, completed a 1 teraflops supercomputer QCDSP for lattice QCD in 1998 and a 10 teraflops QCDOC machine in 2001. Most recently, Lee and R. Friedberg have developed a new method to solve the Schrödinger Equation, leading to convergent iterative solutions for the long-standing quantum degenerate double-wall potential and other instanton problems. They have also done work on the neutrino mapping matrix.
Chen-Ning Franklin Yang (simplified Chinese: 杨振宁; traditional Chinese: 楊振寧; pinyin: Yáng Zhènníng) (born October 1, 1922) is a Chinese–American physicist who works on statistical mechanics and particle physics. He and Tsung-dao Lee received the 1957 Nobel prize in physics for their work on parity nonconservation of weak interaction. Yang became a United States citizen in 1964.
Yang was born in Hefei, Anhui, China; his father Yang Ko-Chuen (Chinese: 楊武之; pinyin: Yáng Wǔzhī) (1896–1973) was a mathematician and his mother Luo Meng-hua (羅孟華) was a housewife. Yang attended elementary and high school in Beijing, and in the autumn of 1937 his family moved to Hefei after the Japanese invaded China. In 1938 they moved to Kunming, Yunnan, where the National Southwestern Associated University was located. In the same year, as a second year student, Yang passed the entrance examination and studied at the National Southwestern Associated University. He received his bachelor’s degree in 1942, the thesis being about the application of group theory to molecular spectra, under the supervision of Wu Ta-you (吴大猷) (1907–2000). He continued to study graduate courses there for two years under the supervision of Wang Chu-hsi (王竹溪) (1911–1983), working on statistical mechanics. In 1944 he received his master’s degree was awarded a scholarship known as the Boxer Indemnity (Chinese: 庚子賠款; pinyin: Gēngzǐ péikuǎn), a scholarship set up by the United States government using the funds raised from the money China was forced to pay out following the Boxer Rebellion. He was delayed for one year, during which time he taught in a middle school as a teacher and studied field theory.
From 1946, Yang studied at the University of Chicago with Edward Teller (1908–2003), where he received his doctorate in 1948 and remained for a year as assistant to Enrico Fermi. In 1949 he moved to the Institute for Advanced Study where he began a period of fruitful collaboration with Tsung-Dao Lee. In 1966 he moved to the State University of New York at Stony Brook and became the Albert Einstein Professor of Physics and the first director of a newly founded Institute for Theoretical Physics which is now known as C. N. Yang Institute for Theoretical Physics.
He retired from Stony Brook in 1999 as Emeritus Professor. In 2010, Stony Brook University honored Yang’s contributions to the university by naming its newest dormitory building Yang College. That same year, he was the honoree at Stony Brook University’s annual Gala of the Stars fundraiser.
He has been elected a Fellow of the American Physical Society, the Chinese Academy of Sciences (中国科学院, People’s Republic of China), the Academia Sinica (中央研究院, Republic of China (Taiwan)), the Russian Academy of Sciences, the Royal Society, etc. and was awarded an honorary doctorate by Princeton University (1958), Moscow State University (1992), Chinese University of Hong Kong (1997), etc.
Yang visited the Chinese mainland in 1971 for the first time after the thaw in China–US relations, and has subsequently made great efforts to help the Chinese physics community to rebuild the research atmosphere which was destroyed by the radical political movements during the Cultural Revolution. After retiring from Stony Brook he returned as honorary director of Tsinghua University, Beijing, where he is the Huang Jibei – Lu Kaiqun professor at the Center for Advanced Study (CASTU).