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(I'm aware treating photon as particle and talking about its position is not exactly, conceptually right but I think it makes sense, at least in the point of view of a beginner. Please just assume photons carry fields and they exist like particles for the moment,or call them anything else if you think it fits better.)

When I study maxwells electrodynamics, I always end up seeing the following image. However I do not really understand what meaning should I make of it. I would really appreciate if you can briefly mention any experiments measuring this electric and magnetic field property, in case its relevant to your answer.

enter image description here (here is the image I encounter)

1- Does it mean a single photon moves and carries fields of varying magnitude? Therefore we experience different electrical and magnetic field depending on at which position we encounter the photon? So by chance, if a point object is just at the place where E=B=0, photon may just pass through without doing anything? I tried to draw it as follows, in case I cannot make myself clear by words. enter image description here (picture 1)

2- Or does it mean, photons travel in groups and their sequence forms a sinusoidal shape. And the whole group goes with c, as in the following clumsy drawing (of course it is drawn discrete but I mean if this image was continuous): enter image description here (picture 2)

I think that all notes I encounter mean the 'picture 1' I have drawn. But it just do not feel right to me with my current knowledge, since varying fields of single photon means effect of a photon to a point charge depends on which phase photon meets the charge although photons were supposed to have a constant energy to give off. And also, if we look at the field distribution with a ray of photons, that would make the field move even faster than c, since photons carry their wave with c but the wave they carry also seems like propagating as it changes with time. Would you explain this mechanism to me, what proof do we have to say this actually happen instead of picture 2 I have drawn? Why do we rule out possibility of picture 2? (the question is not duplicate specifically because this part, and that it tries to relate photons propagation with it)

I know I should be violating some basic concepts but I am trying to learn by questioning and I have already read the existing lecture notes so please bear with me. I am really dying to make a sense out of this electrodynamics but I just cannot do it since no one even attempts to talk about what would a particle correspondence of wave theory would be. I would really appreciate any insights, explanations, corrections or experimental information. Thanks in advance.

ozgeneral
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    Just as a general comment, the precise correspondence between the quantum picture and the classical picture is nowhere near as simple as you're hoping. In fact it is hard enough that I've never seen it written down (mind you, I'm not an optics guy). In particular a single photon can't be represented in terms of linearly polarized waves such as you are drawing here, as the photon has spin-component $\pm 1$ along the direction of travel. – dmckee --- ex-moderator kitten Oct 06 '15 at 19:09
  • The sketch shows the oscillation of a radio wave. And you are right that a single photon could not have the electric and magnetic field equal to zero at the same time. See this post. – HolgerFiedler Oct 06 '15 at 19:28
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    Possible duplicate of What is the relation between electromagnetic wave and photon? – ACuriousMind Oct 06 '15 at 19:54
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    "Please just assume photons carry fields and they exist like particles for the moment,"...asking us to assume something that isn't the case is not a good premise for a physics question. Either you can have the four-potential as a quantum field and the photon as its particle, or you can have the classical picture of electric and magnetic fields. You can't have both, you have to decide whether to do a classical or a quantum treatment of physics. – ACuriousMind Oct 06 '15 at 20:02
  • @ACuriousMind or call them anything else if you think it fits better. You are able to understand my question and welcome to edit it. I am just trying to make sense of the first picture I encountered, and I am not as concerned with precise meanings of terms as you are. At the moment I am trying to make sense of the concept. – ozgeneral Oct 06 '15 at 20:05
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    "and I am not as concerned with precise meanings of terms as you are" - You should be concerned with the precise meanings of terms since otherwise physics is just a bunch of ill-defined words interspersed with non-sensical pictures and formulae. – ACuriousMind Oct 06 '15 at 20:16
  • So tell me what is sensical about the first picture I always encounter. Because what you are doing is not helpful at all, you just dont like my expression and ask me to delete the question. But I still haven't got my answer and surely I wont stop asking just because you think its not sensical. – ozgeneral Oct 07 '15 at 04:40
  • OE1, your first image is a representation of a classical, linearly-polarized electromagnetic wave (either a plane wave or a selected ray of some more complicated geometry), and there is no answer in the form you want because no state of a photon corresponds to such a wave. The super-imposition of photons can corresponds to such a wave, but the particular combination is either infinite (for a plane wave) or very complicated. In all seriousness, you want to master the two descriptions of light separately before trying to develop a quantitative understanding of the correspondence. – dmckee --- ex-moderator kitten Oct 07 '15 at 20:29
  • ozgeneral, if you still active, what do you think today about photons, EM radiation and EM waves? – HolgerFiedler May 28 '21 at 16:10

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The problem for photons is that you cannot observe them time to time. If you do measure their state, photons will collapse to some Eigen state and become classical. In fact, a photon can have a lot of eigenstates in theory. That is special compared to EM for photons.

X Qi
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