Say I have a large spacetime lattice set up on a supercomputer where I calculate the scattering cross section of two spinless electrons of equal and opposite momentum via lattice QED. To get the right results we must add the amplitudes for every possible "path" the field can evolve from initial conditions? Will the most likely "path" of the electron field be one where the spinless electrons do not interact at all (or "hardly at all", small delta p) because of the smallness of electric charge? The interesting physics comes from the relatively small fraction of "paths" where electrons scatter? Thanks for any help!