Kind of a follow-on question…
When a pair of virtual particles are created, how far apart are they (inches, centimeters, cubits, whatever), or do they just appear from a single point traveling in opposite directions (or something)?
That’s not really an answerable question, since particles don’t have well-defined positions to begin with. But to the extent that there’s any relevant length scale, it’d be the Compton wavelength, which for an electron is in the vicinity of 10[sup]-12[/sup] meters.
Could there be a spread in separation? In pair production, lower energy pairs are formed more than higher energy pairs, so lower frequency photons are formed more than higher frequency photons, and for electron-positron pairs, relatively slow-moving pairs are more likely than pairs with high velocity.
Is there a similar spread in position, with pair production more likely for pairs with a small separation as compared with pairs formed farther apart?