Do separate instances of virtual pair production interact with each other. Say you have a virtual pair production of an electron and a positron; they separate and then come back together. What happens in the event that there is another occurrence of a virtual electron/positron pair production nearby the first? Can the electron of the first pair annihilate with the positron of the second pair? I suppose this would mean that the positron of the first pair is left to annihilate with the electron of the second pair, or perhaps some other positron of perhaps a third pair. Is there an electric potential between them? Is there a gravitational force between them? More generally on average for all possible virtual particles of the vacuum energy, does the vacuum energy in a small volume of space have a force on an adjacent volume of space that pulls or pushes it? Is this due to the effects mentioned in the paragraph above? Thanks.