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Is the electromagnetic field quantized?

  1. Jan 16, 2010 #1

    I'm not a physicist. Just trying to get a feeling og matter, space and time without having to do the math (How DO you understand it?!?) Still I have a question.

    Is the electromagnetic field of a particle quantized - except for either being there og not being there? Does - for example - the force between two electromagnetic particles that are moved closer change in discreete values?

    Hope the question is understandable.

    Thanks, Henrik.
  2. jcsd
  3. Jan 16, 2010 #2


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    The field's energy is quantized into quanta called photons. As for the field itself, it's a bit tricky I think. The electric and magnetic fields are observables of the quantum electromagnetic field but they are not the eigenvalues of the field's states. The fields are described by the scalar and vector potentials. So in that sense, while the energy is quantized, the field's electric and magnetic amplitudes can vary though I would expect that their means would be quantized in accordance with the quantization of the potentials and energy.
  4. Jan 16, 2010 #3

    Short answer: no, the field is continuous.
  5. Jan 16, 2010 #4
    The Coulomb force between an electron and a proton, or between any two oppositely charged particles is such that there are only discrete bound states allowed, given by the solutions to either the Dirac equation or Schrodingers equation. The radial force is the derivative of the binding energy W: dW/dr = F(r), so if W(r) is quantized, does this mean that the force is quantized?
    Bob S
  6. Jan 17, 2010 #5

    Vanadium 50

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    After Bob's answer, it's worth repeating "Short answer: no, the field is continuous. "
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