Enrico Fermi was a physicist whose genius bridged the gap between theoretical and experimental physics. He was awarded the Nobel Prize in 1938 for his work on induced radioactivity. After fleeing Italy to the U.S., he led the team that created 'Chicago Pile-1,' the world's first artificial nuclear reactor. This successful experiment proved that a self-sustaining nuclear chain reaction was possible, paving the way for both the atomic bomb and nuclear energy. Fermi was known for his 'Fermi problems'—his ability to make incredibly accurate estimations with minimal data. He is often called the 'Pope of Physics' because he was rarely wrong, and several subatomic particles and elements are named in his honor.