Erwin Rudolf Josef Alexander Schroedinger, Nobel Laureate

Schrodinger invented wave mechanics as an alternative to Heisenberg's matrix mechanics, and was able to find the energy-levels of hydrogen, and also their multiplicity. This result had been achieved by Pauli a few months earlier, by using Heisenberg's formulation. It is often said that Schroedinger showed that his theory was equivalent to matrix mechanics; however, what he really showed was that L² is a separable Hilbert space, and that his theory is a special case of Heisenberg's. The full equivalence only follows from the Stone-von Neumann theorem, which says that the Heisenberg commutation relations, in the form posed by Weyl, has a unique irreducible representation.