You are viewing a single comment's thread from:
RE: Photon-photon scattering detected at LHC!
A photon can temporarily disintegrate into an electron and an anti-electron, before recombining back to form the photon
Actually, the photon do not decay into the electron-positron pair as the latter two guys are virtual particles (and thus not observable). You must see this as a way to take care of the calculations and making predictions. The only think you observe in your detector are the final state particles.
Oops, thanks for the reminder. I think I phrased it badly there. The electron-positron pair are virtual off-shell particles and so exist only ephemerally.
Well, that's actually the point: they don't exist, even ephemerally.
Well, they exist in the sense that they are disturbances of the underlying field. I am not claiming that they can be observed anywhere. In perturbation theory, one still integrates over the virtual particles' momentum to get the amplitudes.
That's a calculation trick. You seem to say,. in your post, that they materalize, but they don't. That's my only point. You could for instance use other techniques going beyond the Feynman diagram approach for taking care of the same calculation and get the same result.