[REBROADCAST FROM MARCH 11, 2021] Post offices across the country are now selling a stamp commemorating female physicist Dr. Chien-Shiung Wu. In the early 1940s, Dr. Wu worked on the Manhattan Project, developing a key process that separates uranium metal into the isotopes used in the atomic bomb. She also disproved the Law of Conservation of Parity, which was thought to be a bedrock principle in physics. Janna Levin, professor of Physics and Astronomy at Barnard College and chair and director of sciences for Pioneer Works, talks about Dr. Wu's groundbreaking work. Dr. Wu's granddaughter, Jada Yuan, also joins us.