The propagation of something, photon or particle, can have many possible paths, thus the Feynman path integral formulation of quantum mechanics. The initial position is relatively fixed and the final position is relatively fixed (compared to all of space). But it's path from beginning to end can be anything. So I wonder how far this concept goes. Does it apply to the first appearing of a particle (or particle creation)? Can the location itself of a particle's initial position when first formed also have many possible locations as well? Would this be quantum field theory? In otherwords, its intial state would be non-existence, its final state would be existence, and every possible path would be replaced with every possible location? thanks.