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The Nature of Photons

  1. Jul 7, 2010 #1


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    I was wondering what the nature of a photon is, when I was thinking about different EM wavelengths.. If you compared the distance traveled by two photons of different energies, wouldn't the more energetic one travel a longer distance (assuming they have the same amplitude)? It seems like it would be something akin to two people running across a surface modeled to resemble the wave nature of light. If the runners were the photons running across the waves, the runner running across the the more 'energetic' landscape would have to cover a longer distance and a greater speed to keep up (move at c) with the 'photon' moving across the surface with a shorter amplitude. Wouldn't it have to move faster than c?
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  3. Jul 7, 2010 #2


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    Staff: Mentor

    Are you thinking that a photon moves side-to-side along a "wavelike" path as it moves forward? It doesn't do that. In a diagram of the electromagnetic field as a wave, the vertical axis doesn't represent position, but rather the strength of the field.
  4. Jul 7, 2010 #3


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    Ooooohh, ok. I did some more reading. That makes sense. Well, that was easy. Thank you :)
  5. Jul 9, 2010 #4
    say jtbell...is the wave function the best way to answer this question?

    I was thinking about an example of relativity...where a train is moving almost exactly at the speed of light....say...1 foot per second slower than the speed of light. Well a little girl runs forward in that train but wont break the speed of light....because the time function will slow her down. So, as she approaches the 1 foot per second....she slows down in time...never exceeding that 1 foot per second.

    I think it is the same with energetic photons or particles.

    I think introducing the wave function to this question just gets completely disconbobulating.

    Is that right or am I way off?
  6. Jul 9, 2010 #5
    It is right that the girl in your example wouldn't reach lightspeed (although your
    understanding of the reason why seems a little bit confused). It is wrong that
    this reasoning is a better way to address the OP's question, though, or in fact
    that it answers it in any meaningful way. The OP's question was motivated by
    an incorrect mental model of the propagation of photons as little balls moving
    up and down in a wavelike movement; jtbell's reply was directed at clearing
    the OP's misconception, which was the cause of his confusion.

    As an aside, there's no mention to (quantum) wave functions anywhere in jtbell's
    post; the waves he and the OP are referring to are just electromagnetic waves.
  7. Jul 9, 2010 #6
    Oh I think I see....I thought "strength of the field" was wave function
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