Werner Heisenberg foundation of the matrix formulation of quantum mechanics through only the use of observables. In February 1943, Heisenberg was appointed to the Chair for Theoretical Physics at the "Friedrich-Wilhelms-Universität" (today, the Humboldt-Universität zu Berlin). In April, his election to the "Preußische Akademie der Wissenschaften" (Prussian Academy of Sciences) was approved. That same month, he moved his family to their retreat in as Allied bombing increased in Berlin. In the summer, he dispatched the first of his staff at the "Kaiser-Wilhelm Institut für Physik" to Hechingen and its neighboring town of Haigerloch, on the edge of the Black Forest, for the
Heisenberg group unitary operator of formula_103 that commutes with them is an formula_121 multiplier. But commuting with translations implies that the multiplier is constant. A version of the Stone–von Neumann theorem, proved by George Mackey, holds for the Heisenberg group formula_113. The Fourier transform is the unique intertwiner between the representations of formula_103 and formula_124. See the discussion at Stone–von Neumann theorem#Relation to the Fourier transform for details. Heisenberg group In mathematics, the Heisenberg group formula_1, named after Werner Heisenberg, is the group of 3×3 upper triangular matrices of the form under the operation of matrix multiplication. Elements "a, b" and "c"