(Correct where applicable)

The electromagnetic field can be interpreted as a representation of the magnitude and direction of the force photons will have on another charge.

The path a photon takes is the field line (and yes, according to quantum physics a photon takes all possible paths until its wave function breaks down, so the field line of a single photon will have all possible shapes before the wave function collapses).

So can the field lines intersect if the light is concentrated, causing the photons to converge upon a point, despite the electromagnetic field intensity having more than one value if the field lines converge?

  • $\begingroup$ Related question by OP: physics.stackexchange.com/q/441886/2451 $\endgroup$ – Qmechanic Nov 19 '18 at 6:52
  • $\begingroup$ @Qmechanic, not really. Both questions are about the convergence of photons, but that is where the similarities end. This question is about trying to understand how field lines can converge without having more than one value of electromagnetic intensity, or to see where I am wrong in my knowledge.---------- The other question is essentially if gravity can change the direction of photons without any process of absorption and emission. $\endgroup$ – Abdul Moiz Qureshi Nov 19 '18 at 7:03

You have a wrong understanding of the relationship between the electromagnetic field and photons. Photons are the quanta of the electromagnetic field.

The field lines are not the paths of photons. For example, if you have a single charge at rest, it has an electric field, and you can picture that field as having field lines, but there are no photons traveling along them.

There is no “field line of a single photon”.

Electric field lines converge or diverge only where there is charge density, and magnetic field lines never converge or diverge at all. This is what two of Maxwell’s equations,




tell us.

You should first learn classical electromagnetism thoroughly, such as what Maxwell’s equations mean, and then learn about the quantum version of electromagnetism, which is harder. Trying to learn about both at the same time tends to lead to confusion.

  • $\begingroup$ "Photons are the quanta of the electromagnetic field."-------- I've always read the that photons are the quanta of the waves of the electromagnetic field. $\endgroup$ – Abdul Moiz Qureshi Nov 19 '18 at 6:45
  • $\begingroup$ Read the first sentence of this: en.m.wikipedia.org/wiki/Photon $\endgroup$ – G. Smith Nov 19 '18 at 7:05
  • $\begingroup$ Real photons are associated with waves. “Virtual photons” are not necessarily associated with waves. $\endgroup$ – G. Smith Nov 19 '18 at 7:16
  • $\begingroup$ Okay. But why would photons be present when the electromagnetic field is not accelerating? Virtual particles are not proven, but are a mathematical possibility of quantum physics, and besides, are not produced by the point charge, but by spacetime flunctuations, so why would they relate to the field of the point charge? $\endgroup$ – Abdul Moiz Qureshi Nov 19 '18 at 8:21
  • $\begingroup$ The electromagnetic field does not accelerate. Acceleration implies motion of somethng from one place to another place. A field exist at all places at all times. Its value at a point can change with time, but this isn’t called acceleration. $\endgroup$ – G. Smith Nov 19 '18 at 18:21

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