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Frequency of the polarization of light

  1. Jan 27, 2012 #1


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    "Frequency" of the polarization of light

    You often see the polarization of light represented this way:

    Unfortunately, the axis is seldom labeled in this type of animation. I assume the horizontal axis is meant to represent space or time. The question I have is "Does the fluctuation frequency of the electrical field match the wave length of the photon?"

    To be a little clearer, if you have a photon with quite a long wavelenth (say microwave at 21cm), the wavelength represents the changing probability of things like the photon being reflected when it hits a surface. I assume that the magnetic/electrical fluctuation represented by this picture happens much faster over a much shorter distance then 21cm.

    Is that assumption correct, or does the electrical/magnetic fluctuation rate of the photon match its frequency?
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  3. Jan 27, 2012 #2


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    Re: "Frequency" of the polarization of light

    To my knowledge the wavelength is the distance that the light travels in 1 cycle of its changing electric and magnetic fields while the frequency is how many times it switches per second.
  4. Jan 27, 2012 #3


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    Re: "Frequency" of the polarization of light

    Wiki actually has some pretty good animations on this:

    One cycle of the oscillating magnetic or electric field is one wavelength, yes. Frequency is 1/wavelength.
  5. Jan 27, 2012 #4
    Re: "Frequency" of the polarization of light

    Wavelength in free space (meters per cycle) * frequency (Hz : cycles per second) = c (speed of light in meters per second)
  6. Jan 28, 2012 #5


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    Re: "Frequency" of the polarization of light

    I also like the graphics on this page http://en.wikipedia.org/wiki/Polarizer

    So there is nothing wrong with labeling a 532nm photon moving though space scaled in nanometers like this:

    And the photon varies in time scaled by zeptoseconds like this:

    This certainly makes things like newtons rings easier to understand. It also makes it pretty obvious why the probability of reflection off a surface varies depending on how far the photon travels to get to this surface. The only thing I dont like about these animiations is the use of the second axis for the amplitude. You can model reflection in one dimension this way, but you cannot model refraction as the second and third axis are already in use.

    Finally, does this not specifically tie down the location of the photon to a particular point in space at a particular time? Is this a violation of the uncertainty principle?
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