Werner Heisenberg allotropic forms of hydrogen". Shortly after the discovery of the neutron by James Chadwick in 1932, Heisenberg submitted the first of three papers on his neutron-proton model of the nucleus. After Adolf Hitler came to power in 1933, Heisenberg was attacked in the press as a "White Jew". Supporters of "Deutsche Physik", or Aryan Physics, launched vicious attacks against leading theoretical physicists, including Arnold Sommerfeld and Heisenberg. From the early 1930s onward, the anti-Semitic and anti-theoretical physics movement "Deutsche Physik" had concerned itself with quantum mechanics and the theory of relativity. As applied in the university environment, political factors took
Heisenberg model (quantum) Assuming that there's only one critical point, we can conclude that the phase transition happens at formula_22. It is common to name the model depending on the values of formula_23, formula_24 and formula_6: if formula_26, the model is called the Heisenberg XYZ model; in the case of formula_27, it is the Heisenberg XXZ model; if formula_28, it is the Heisenberg XXX model. The spin 1/2 Heisenberg model in one dimension may be solved exactly using the Bethe ansatz. In the algebraic formulation, these are related to particular Quantum affine algebras and Elliptic Quantum Group in the XXZ and XYZ cases