This is a layman. I have a question about Feynman diagram. The Feynman diagram depicts an interaction between two electrons in a way in which one electron emits a photon and then after a little time the other electron receives and absorbs that photon.
The question that I would like to ask is this.
How can an electron generate and emit a photon? Does an electron have its internal structure in which some kind of electromagnetic wave-generating device is involved? What sort of event triggers the emission of a photon? The QED (Quantum Electro Dynamics) theory does not explain the mechanism of such a photon emission or photon absorption by an electron.