How do we know that charges interact by photons? Has it been observed or is it an assumption in quantum electrodynamics?

  • $\begingroup$ en.m.wikipedia.org/wiki/Quantum_electrodynamics gives a pretty good review of the subject. I am sorry, but I am not sure what you mean by is it an assumption, given the prevalence of electric devices in the world today. $\endgroup$ – user108787 Aug 21 '16 at 10:54
  • $\begingroup$ @count_to_10 In that wikipedia article it is given, " The images are just symbols to represent the actions above: photons and electrons do, somehow, move from point to point and electrons, somehow, emit and absorb photons. We do not know how these things happen, but the theory tells us about the probabilities of these things happening." for feynman diagrams. $\endgroup$ – Rick Aug 21 '16 at 11:01
  • $\begingroup$ I would agree with that, in the same way we measure the speed of light, but we have no idea why it is the value it is. Photons, electrons, etc are just names for entities with certain distinctive properties that we can measure but as far as fully understanding them, we don't. The thing we can be happy about is that our predictions are confirmed by experiment, as in integrated chip design. If predictions and experimental results don't match, then we have trouble, but so far, so good. $\endgroup$ – user108787 Aug 21 '16 at 11:14

The force carriers between two charges are virtual photons which cannot be directly observed. However, the theory that describes this interaction (QED) does make many predictions that have been experimentally confirmed with incredible precision, see Wiki: Precision tests of QED.


How do we know that charges interact by photons? Has it been observed ...?

It is observed that during the approach of an electron to the nucleus photons are emitted and it is observed that During the exposition of atoms by EM radiation electrons could be released from the nucleus.

Furthermore it is observed that during the deflection of moving electrons in an external magnetic field this electrons emit photons.

What is observed throwing two electrons to each other? They loose at once their velocity and spread out again. No EM radiation is observable. To explain the varying forces one could use the imagination of virtual photons. For an other than explanation we have to define the electric field as real and to give this field the characteristics of "where one body is an other body can't be" in analogy to elastic bodies.

The problem is that our today's curiosity stops in front of the question from what an electric as well as a magnetic field is made.

  • $\begingroup$ Are photons composed particles is a hypothesis of mine about the nature of electric field, magnetic field and EM radiation and it is helpful for deeper understanding of electromagnetism. $\endgroup$ – HolgerFiedler Aug 29 '16 at 14:34

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.