Heisenberg picture formulation of matrix mechanics in an arbitrary basis, in which the Hamiltonian is not necessarily diagonal. It further serves to define a third, hybrid, picture, the interaction picture. In the Heisenberg picture of quantum mechanics the state vectors, |"ψ("t")"〉, do not change with time, while observables satisfy where is the Hamiltonian and <nowiki>[•,•]</nowiki> denotes the commutator of two operators (in this case and ). Taking expectation values automatically yields the Ehrenfest theorem, featured in the correspondence principle. By the Stone–von Neumann theorem, the Heisenberg picture and the Schrödinger picture are unitarily equivalent, just a basis change in Hilbert space. In
Werner Heisenberg and the whole"). Heisenberg died of cancer of the kidneys and gallbladder at his home, on 1 February 1976. The next evening, his colleagues and friends walked in remembrance from the Institute of Physics to his home and each put a candle near the front door. He is buried at Munich Waldfriedhof. Heisenberg was awarded a number of honors: The following reports were published in "Kernphysikalische Forschungsberichte" ("Research Reports in Nuclear Physics"), an internal publication of the German "Uranverein". The reports were classified Top Secret, they had very limited distribution, and the authors were not allowed to keep copies. The