J. Robert Oppenheimer was an American theoretical physicist, known as the "father of the atomic bomb." He served as the director of the Los Alamos Laboratory during the Manhattan Project, leading the development of the first nuclear weapons. Oppenheimer was born in 1904 in New York City, studied at Harvard and Cambridge, and made key contributions to quantum mechanics. His work shaped nuclear physics, but he later faced controversy during the Red Scare. He died in 1967, leaving a legacy in science and history.