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Asymmetric B and E

  1. Jul 15, 2011 #1
    B and E are typically illustrated in a symmetric phase shifted oversimplified sine wave(s).

    Are the B and E waves ever non-symmetrical to one another? This seems to make no sense to me, as they induce one another.

    Also EM waves do not always involve the release of photons, correct? I was once told the easiest way to make a Electromagnetic wave was to comb your hair(get a charge on comb), then wave the comb up and down. By definition this movement of charge generates an Electomagnetic wave, no photons released here as charge moves up and down, correct?

    Thanks for any clarification!
  2. jcsd
  3. Jul 15, 2011 #2


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    B and E are perpendicular, shifted in phase, as you said, etc. only at long distance from EM source, where you may see them as a propagating flat wave approximation. Closely to the antenna they may be related differently. They may also not be perpendicular if the wave propagates through anisotrobic medium (the one rotating polarisation, like glucose solution for visible light)

    Of course, waving your comb you release billions of photons! Waving the comb you emit some EM wave (honestly: not a strong one...), which carries the energy. This energy may be seen as a number of photons.
    Anyway, for such experiments classical Maxwellian electrodynamics seems to be much more suitable approach.
  4. Jul 15, 2011 #3
    Thanks! I originally had a EMP question regarding Greater E field than B field. This seemed to make no sense to me.

    I actually should have said are B and E ever non-symmetrical in size and shape (under the curve). This would make no sense since one induces the other.
    Last edited: Jul 15, 2011
  5. Dec 14, 2011 #4
    I had this conversation with retired U.C.C.S. Physics Professor Bobby Bracewell last weekend. He thought Permeability of the medium could also create non-symmetrical waves. Any thoughts?
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