Chien-Shiung Wu

Born near Shanghai, she came to the University of California, Berkeley in 1936, worked on the Manhattan Project at Columbia, and became one of the finest experimental physicists of her time, nicknamed the 'First Lady of Physics'.

In 1950 she and Irving Shaknov measured the polarisation of the two gamma-ray photons produced when an electron and a positron annihilate, and found them correlated in the way quantum theory required. It is often regarded as the first laboratory observation of correlations between entangled photons, and was cited by the later Bell tests.

Her best-known experiment, in 1956–57, showed that the weak nuclear force breaks mirror symmetry (parity). Her colleagues T. D. Lee and C. N. Yang received the Nobel Prize for proposing the idea; she did not.

Wu's work is a reminder that quantum theory is not only a history of equations; it was built as much by experimenters who found ways to make the strange predictions visible. The omission of her name from the 1957 Nobel Prize is one of the best-known oversights in the prize's history.