In an effort to understand how an electron and proton attract each other in the QFT picture, I am wondering if there any differences at all between photons (virtual or whatever) emitted by electrons and photons emitted by protons? For instance, do photons from protons have a different spin or polarization than those emitted by electrons? Are they out of phase or something? Do photons from protons tend to make electrons emit photons, whereas photons from electrons that hit other electrons tend to make those electrons absorb the photons? Anything like this?