Huh?? This is called pair production and doesn't need an accelerator. Nor does this tell us the mechanisim that allows two photons to become a tangible electron or positron. If this were any other experiment, what do we presume when we see two oppositely charge particles exit the same spot in space. Answer - we presume that there was a precusror neutral particle. This is how we detect all neutral particles such as the neutral Delta Baryon. We DO NOT presume that the observed oppositely chraged particles were "created". Why is it we think that pair production is the exception? The Lamb Shift experiment strongly points to the possiblity that vacuum space is filled with a sea of positive and negative charges. Could this be the source of the observed positron and electron?