Other, more subtle differences show up in the symmetry properties of weak and electromagnetic interactions.
But even in the 1950s there was one apparent similarity between weak and electromagnetic interactions.
They knew that the electromagnetic interaction takes place via the exchange of a photon (figure 2).
So for another few weeks or months the question of the unification of weak and electromagnetic interactions is still open.
According to this theory, there was not much difference between weak, strong and electromagnetic interactions in the very early universe.
When there is a charged condensate, the electromagnetic interactions are screened.
He made fundamental contributions to quantum theories of electromagnetic interactions with atoms.
Fundamental electromagnetic interactions occur between any two particles that have electric charge.
Technically all electromagnetic interactions are by way of photons, real or virtual in the end.
Minimal coupling is a simple way to include the electromagnetic interaction.