[问答题]
Show, by conserving momeivgg: *y h -m:/tawd3qntum and energy, /f)9.pzrppu) 0fsn hw that it is impossible for an isolated elez)nuh9.p pfpr) 0/wsfctron to radiate only a single photon. (b) With this result in mind, how can you defend the photon exchange diagram in (Fig. Below)?
