Approximation Method for Short Wavelength or High-Energy Scattering

The approximation method developed in a recent paper is extended to the scattering theory of Maxwell's equations and of the Schr\"odinger equation with spin-orbit interaction. Both of these situations are more complicated than the Schr\"odinger and Dirac cases considered earlier. However, while the electromagnetic case yields the earlier type of result in which the Born formula is modified by the inclusion of an additional phase factor, the Schr\"odinger spin-orbit case cannot be put in such a simple form. Brief mention is also made of the tensor interaction, which is even more complicated than the spin-orbit interaction, and of the space-exchange interaction, which can be treated by this method only if the potential is symmetric with respect to inversion.