Inclusion of Breit-Pauli Short-Range Interactions in the Quantum Mechanical Theory of Sub-Atomic Systems

Following the introduction of the Schrödinger and Dirac quantum mechanical equations for the description of hydrogenic atoms, there was a longstanding attempt to develop a similar approach which is applicable to the treatment of nuclear reactions. There was consensus that interactions of shorter range than the Coulomb force are involved, but there was also the strongly held view that the corresponding Hamiltonian that satisfies this requirement must be invariant to a Lorentz transformation. The latter conclusion is questioned on the basis of a simple example involving the interaction of an electron in an electromagnetic field