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Photon Size

  1. Feb 9, 2007 #1
    In visible light, what is the spatial dimensions of the photon itself. I'm interested in the experiments they have done to prove how big the photon is.
  2. jcsd
  3. Feb 9, 2007 #2


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    In most cases, a photon is described by its wavelength and has physical properties that relate to that. Visible light is roughly in the range of 350 to 750 nanometers (10^-9 meters).

    Naturally, there have been any number of experiments that connect wavelength to some of these physical properties. Is there any specific "size" property you are trying to understand? Other than wavelength, a photon does not have another parameter that relates to size in the normal sense of the word. (As a quantum particle, it is bound by the Heisenberg Uncertainty Principle. It is otherwise considered to be a point particle in much the same fashion as an electron.)
  4. Feb 9, 2007 #3


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  5. Feb 10, 2007 #4
    Thanks you guys. I had devised a little experiment myself. I didn't get into detail about it but basically you shine a laser against a solid object. If the size of the photon is smaller then an atom it should shine brighter in the crack where the laser and object meet and it would through the object. Of course the object would have to be ideal for the amount of light it let through also.
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