Basically talking about Coulomb interactions here, and how they could happen without definite particle positions since Coulomb repulsion or attraction depends on distance which depends itself on positions thus localization. I heard virtual photons is the QM substrate of electrostatic interactions, thus the use of this term in the question. But the point here is more general: how can there be interactions among delocalized objects without collapsing them to a definite position? I heard that probability clouds were once thought to represent actual density functions of the particles but that was later refuted (I don't know how though and if one could slip an answer to this too I'd be glad). So the particle is NOT everywhere in the cloud, it is just somewhere there. Thus how are interactions and possible emissions of gravitational or other force carriers, possibly computable or even real with undefinite positions? I can imagine a cloud of particles acting as a single man, producing radiations that do not allow to extract any inner structure of the particles network (just as sound waves do not convey sufficient information to detail everything about the sources of sound because of superposition, masking, etc). But what about particles interaction among them? How can a virtual photon goes from an undefinite origin to an undefinite destination? Or is it that such photon wavelength encompass the entire particle probability cloud?
Note: I used the word cloud for two different objects (probability of finding a particle somewhere, vs. a set of particles delocalized in a same ensemble/gas), I trust you will notice they are unrelated.