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Why photons reflect off glass?

  1. Aug 10, 2015 #1
    Why photon reflects and refracts through glass? Some photons pass through glass and some reflects.I know this is due to energy levels of electrons of glass, an incoming photon is unable to excite the electron to a different energy orbit.

    But I want to know, if an incoming photon is unable to excite an electron, then why not all the photons pass through glass? i.e. photons should not reflect off glass, all the photons should pass through glass.
     
  2. jcsd
  3. Aug 10, 2015 #2

    ZapperZ

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    You might want to start by reading this, especially in correcting your idea about atomic transition, and how solids are different than atoms.

    https://www.physicsforums.com/threads/do-photons-move-slower-in-a-solid-medium.511177/ [Broken]

    Zz.
     
    Last edited by a moderator: May 7, 2017
  4. Aug 10, 2015 #3
    That doesn't explain what I'm looking for.
     
    Last edited by a moderator: May 7, 2017
  5. Aug 10, 2015 #4

    ZapperZ

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    I said that it is a start, because it should dispel the idea that this is an "atomic transition" phenomenon, and that you need to be aware of a collective behavior when a solid is formed.

    A "reflection" can be caused by a number of phenomena. The simplest of which is a photon scattering off the lattice.

    Zz.
     
  6. Aug 11, 2015 #5
    <<Moderator note: Originally posted as duplicate thread. Removed content identical to the first post.>>

    Is this due to atoms of different substances like water,glass or wood etc curve spacetime differently and thus it influences how photons interact with matter? i.e. some photons reflect and some refract.
     
    Last edited by a moderator: Aug 12, 2015
  7. Aug 11, 2015 #6

    bcrowell

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    This is classical physics, so you might want to work on understanding the classical description before worrying about how the description in terms of quantum field theory reduces to it in the classical limit. If you need help with that, the classical physics forum would be the place to ask.

    No, this has nothing to do with general relativity. Rays of light follow geodesics when there is no other interaction besides gravity. Here gravity is negligible, and the dominant interaction is electromagnetic.
     
  8. Aug 11, 2015 #7

    Orodruin

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    This is a common and extensive problem among laymen who read their share of popular science. The message conveyed seems to be that light are photons, which are small balls of light that should behave similar to how balls behave on a classical level. Nowhere in popular science is it mentioned that gauge theories are about as complicated as it gets when it comes to quantisation and that many of the properties of light is easiest explained in the classical limit.
     
  9. Aug 11, 2015 #8

    bhobba

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    As Zapper correctly points out what's going on is a bit complicated. However at the beginning level, provided you realise it is a simplification, then Feynmans book is a good one:
    https://www.amazon.com/gp/product/0691164096

    Thanks
    Bill
     
    Last edited by a moderator: May 7, 2017
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