According to QFT, virtual electron-positron pairs are created everywhere in the space, and more frequently near electric charges. Suppose that one such a pair is created in the proximity of an electron. Is it possible for the initial electron to annihilate with the created positron, leaving behind the created electron?
If so, the position of the created electron would not be the same as the initial electron, so this effect would change the position of the electron we observe in that region of the space, creating some kind of uncertainty in position. Is there any quantitative measure of such an uncertainty in position due to vacuum fluctuations?