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Why can't light go thru solids?

  1. Sep 13, 2009 #1
    With the huge distances between atoms, relative to the size of the atoms, why aren’t photon packets able to travel through most “solids”? Why are those same photon packets able to travel through many liquids?
  2. jcsd
  3. Sep 13, 2009 #2
    I found your question interesting quantumh20.
    Sorry I don't have an answer for you just another question because of your question.
    Are transparent liquids non-transparent to a different part of the spectrum than solids?
  4. Sep 13, 2009 #3


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    You might want to start by reading one of the FAQ entry in this forum (General Physics) on photon transport in matter. It is a "start", since there are many other factors involved in optical conductivity in solids.

  5. Sep 13, 2009 #4
    "On the other hand, if a photon has an energy beyond the phonon spectrum, then while it can still cause a disturbance of the lattice ions, the solid cannot sustain this vibration, because the phonon mode isn't available. ... So the lattice does not absorb this photon and it is re-emitted but with a very slight delay. This, naively, is the origin of the apparent slowdown of the light speed in the material. The emitted photon may encounter other lattice ions as it makes its way through the material and this accumulate the delay."

    Where does the photon go while it is waiting to be 're-emitted'?
  6. Sep 13, 2009 #5


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    The energy goes into vibrations of the solid (phonons) while it's "waiting".
  7. Sep 13, 2009 #6
    Sounds similar to the action with electrons.
    Is it? Does it mean, in a similar vein, that the photon disappears and a new photon is emitted with each interaction; as it does when an electron absorbs the photons energy and gains that energy? Or is that not right? I'm still not sure where your answer is on this even with your explanation I apologise.
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