The Nobel Prize-winning physicist who contributed to the Manhattan Project was Richard Feynman. Feynman was a prominent American physicist known for his work in quantum mechanics and particle physics. During World War II, he joined the Los Alamos Laboratory, where scientists were developing atomic weapons. His intellect and innovative thinking were crucial in solving various complex problems related to the project. Later, Feynman's contributions to science earned him the Nobel Prize in Physics in 1965, and he became celebrated not only for his scientific work but also for his engaging teaching and communication style.