I have been trying to better understand the concept of a photon (I know...a thousand threads on this alone) and the direction that it propagates. I understand the time-varying field explanation for em waves, but here is where I break down. If an electric field extends in all directions simultaneously, why should we consider that photons have a given direction (unless we physically manipulate it at a given point in space), and also describe photons as occurring in a finite amount? (I'm thinking that a spherical wave could be divided infinitely). Or, maybe I can word it this way -- why would a vibrating charge not also radiate an em wave in all directions? I can't understand how a spherical wave could be considered as discrete packets traveling in random directions. Thanks in advance!