Feynman, photons and magnetic fields

AI Thread Summary
Richard Feynman describes the magnetic field's effect on electrons by suggesting it consists of many photons, raising questions about the nature of photons as oscillating electromagnetic fields. A static magnetic field does not contain real photons, unlike electromagnetic waves that require both electric and magnetic components. While virtual photons can be introduced in perturbation theory, this approach is not ideal for representing a static magnetic field in quantum mechanics. Feynman's explanations often aimed to simplify complex concepts, which can lead to misunderstandings. The discussion highlights the challenges in reconciling Feynman's popular interpretations with the rigorous definitions in physics.
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In one of his lectures Richard Feynman describes the effect of a magnetic field on an electron. In doing this he describes the magnetic field as being made up of many photons. If a photon is an oscillating electromagnetic field how can it be just a magnetic field also ?
 
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A static magnetic field does not have real photons as in an EM wave, which needs both E and M (hence "EM"). In some ways of calculating
(perturbation theory), mathematical virtual photons could arise, but that is an awkward way to treat a static magnetic field, even in QM. Feynman, especially in some popular expositions, liked to jazz things up a bit.
 

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