In June 1925, twenty-three-year-old Werner Heisenberg, suffering from hay fever, retreated to a small, treeless island in the North Sea called Helgoland. It was there that he came up with one of the most transformative scientific concepts: quantum theory. Carlo Rovelli, one of our most celebrated scientists, tells the extraordinary story of quantum physics and reveals its deep meaning. A stunning book about the enigma of quantum physics.