Born in China in 1912, Chien-shiung Wu came to the United States to study physics at the University of California at Berkeley. A meticulous researcher, she joined her former professor, Dr. Oppenheimer, on the Manhattan Project to find ways to produce radioactive uranium for the atomic bomb and improve radioactive detectors. Establishing herself as a world-renowned experimentalist in nuclear physics, Wu was asked by two top theoretical physicists, Tsung-dao Lee and Chen Ning Yang, to see if a "fundamental truth" of physics was wrong. Her confirmation of nonparity in weak forces—that is, that right and left symmetry do not exist when atoms are in a weakened, less stable state—rocked the physics world. Until that point, physicists had assumed that parity—equality between the left and right sides of an atom—existed in all states. Madame Wu, as she was called, was one of the most distinguished women physicists of her time and served as the first female president of the American Physical Society in the 1970s.