I am curious on what is meant by amplitude in an EM wave. From all the searching I have done the amplitude has something to do with the density of photons in the EM wave, and the frequency with energy of the photons. The part I am confused about is the fact that the wave is oscillating. I believe it's not correct to say there is displacement of the photons in such a way that you can characterize it by a distance measurement? I think of the EM wave as this. To me that makes much more sense. I don't want to add any more since any answer to this may change my questions or eliminate them. Thank you for reading this!