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Question about the Source of Electromagnetic Waves

  1. May 18, 2010 #1
    Can anyone tell me what Maxwell said is the source of electromagnetic waves? I read that accelerating charges produce EM waves; are there any other sources?
  2. jcsd
  3. May 18, 2010 #2


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    In classical electromagnetics, no. In classical electromagnetics, only charges and currents are the available sources. In quantum theory we allow for other sources such as the change in energy state of an atom or phonon which emit photons when the excited state drops down to a lower energy state.
  4. May 19, 2010 #3
    In other words: the energy of the E and B fields gets thrown back into a configuration where it is available to excite the charge's motion enough to induce radiation?
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