3 ms·

Dumb question but is this unexpected because photons are bosons?

• orbifold 8y ago
  This is not unexpected, QED (quantum electrodynamics) predicts this. Classically it does not happen because classical electromagnetic fields are in linear superposition. QED has loop diagrams involving virtual fermions that mediate scattering, this is also the reason why these events are rare.
  • gus_massa 8y ago
    I agree. More details: The main problem is that photons only can interact with charged particles, but photons have no charge, so the photons don't interact (directly) with photons. The gluons that are the bosons of the strong force can interact between them, so it's not a problem of bosons vs fermions. In particular, gluons have color that is the equivalent of charge for the strong force. The idea is that the photons can sometimes create a virtual electron-positron pair that is very short lived [1], and the other photon can colide with the electron or positron before they annihilate. This is very rare, and you can ignore it unless you have a really huge amount of photons flying around. [1] Insert here a technical remark about "virtual" and "very short lived". It's more complicated. Take this as a metaphor to hide a lot of math.