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
Max Planck Institute for Physics over as managing director. In 1955 the institute made the decision to move to Munich, and soon after began construction of its current building, designed by Sep Ruf. The institute moved into its current location on September 1, 1958 and took on the new name the Max Planck Institute for Physics and Astrophysics, still with Heisenberg as the managing director. In 1991, the institute was split into the Max Planck Institute for Physics, the Max Planck Institute for Astrophysics and the Max Planck Institute for Extraterrestrial Physics. The current directorial board of the institute is Former directors of the institute