Werner Heisenberg mechanics formulation of quantum mechanics. On 1 May 1926, Heisenberg began his appointment as a university lecturer and assistant to Bohr in Copenhagen. It was in Copenhagen, in 1927, that Heisenberg developed his uncertainty principle, while working on the mathematical foundations of quantum mechanics. On 23 February, Heisenberg wrote a letter to fellow physicist Wolfgang Pauli, in which he first described his new principle. In his paper on the principle, Heisenberg used the word ""Ungenauigkeit"" (imprecision), not uncertainty, to describe it. In 1927, Heisenberg was appointed "ordentlicher Professor" (professor ordinarius) of theoretical physics and head of the department of physics
Jochen Heisenberg comment on Michael Frayn's well-known play "Copenhagen" and has published his perspectives on his father's activities. He currently maintains an informational website containing biographical information and reference material on Werner Heisenberg. Jochen Heisenberg Jochen Heisenberg (born 16 May 1939) is a German physicist specializing in nuclear physics, and Professor Emeritus of Physics at the University of New Hampshire. He is the son of Nobel Prize-winning physicist Werner Heisenberg, who is best known for the uncertainty principle. He is the brother of German neurobiologist and geneticist Martin Heisenberg and the uncle of film director Benjamin Heisenberg. Heisenberg studied physics with Willibald