Hello, I am facing a paradox, well it seems like one, resolving the interaction force between two equally charged plates each bearing a positive charge. Let us assume this as Q, and plates having area A. On one hand , we can claim the force = Q^2/2Ae0 where e0 is the vacuum permittivity, as each plate bears a charge Q and generates a field Q/2Ae0 at points not too far off from itself or close to the edges. But, if we look at the energy stored, I am getting a very different result. There is no field in the region between the two plates so the energy field density 1/2e0(E^2) is zero. Outside the plates, the electric field will remain ~ Q/2Ae0 from each plate, totalling Q/Ae0 at first and then begin trailing off as we go farther and farther. Eventually it will trail off completely. So if we move a plate, this trailing off merely starts at a different point and the net energy stored outside each plate is conserved. Hence energy is a constant therefore F = -dE/dr = zero. I can't accept this logically but neglecting the fringe field, this seems to imply some sort of internal screening of charges.