Heisenberg, Werner (1901–76)

One of the most outstanding of twentieth-century physicists, Werner Heisenberg is famous for the uncertainty, or indeterminacy, principle of quantum mechanics, widely interpreted as implying an irreducibly indeterministic conception of nature. The main proponent of the Copenhagen interpretation after Bohr, Heisenberg conceived of the quantum description as referring not to objective spacetime realities, but merely to the probable outcomes of measurements. Heisenberg’s philosophy, containing contradictory positivistic and realistic strands, is best understood in the context of his creative scientific theorizing.