- #1
kelly0303
- 563
- 33
Hello! As far as I understand, in QFT the interaction between particles is mediated by the exchange of a boson. When doing calculations, one assumes that you have 2 free particles coming in, they interact at a point by exchanging a boson and then they propagate again as free particles, and this is the image the Feynman diagrams show, too. However, (say in the case of 2 electrons) the interaction doesn't take place only once. The electrons feel the effect of each other all the time, so I would imagine that a diagram reflecting this should have a photon exchange at each point along the 2 electron lines. Is this continuous interaction mathematically equivalent to just one interaction at a given point? Or how should I think about the Feynman diagrams? Thank you!