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Photon emission from dipole antenna

  1. Jun 4, 2015 #1
    Are photons emitted from the stationary protons in a dipole antenna? The protons don't accelerate at any point but their electric field does contribute to the electromagnetic wave.
    Last edited: Jun 4, 2015
  2. jcsd
  3. Jun 5, 2015 #2


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    Photons are the energy quanta of the (classical) EM wave and one of the known sources of EM wave is the antenna.
    Are protons the only charged entity inside the metal making up the antenna?
  4. Jun 5, 2015 #3


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    It's impossible to make usual antennas to emit single-photon (Fock) states. What you'll emit are coherent states, which are more like a classical electrical wave than single-photon Fock states. If dimmed down to intensities with average photon numbers close (or even less than) one, the coherent state consists to a large amount of the vacuum state. With some small probability you may register one or (to even lesser probability) more photons in a statistical way. The probability distribution for the photon number in such a coherent state is the Poisson distribution,
    $$P(N)=\frac{\lambda^N}{N!} \exp(-\lambda),$$
    where ##\lambda## is both the average number ##\langle N \rangle=\lambda## of registered photons as well as its standard devition ##\langle N^2 \rangle -\langle N \rangle^2=\lambda##.
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