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Is it possible to slow down/stop the light?

  1. May 22, 2013 #1
    I actually don't have much information about the topic "light" that's why i would appreciate it if you explain a little bit detailed.

    Edit: Light cannot directly go to B. There is a solid block between them.

    Would it be possible to build such a system? Is there a material that slows down the light?
    Or is it possible to trap or freeze an exact moment of display, just like photos, but the actual display?
    Last edited by a moderator: May 6, 2017
  2. jcsd
  3. May 22, 2013 #2


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    Staff: Mentor

    Every material slows light, but even if its speed is reduced by a factor of 3, it is still going at 100,000 kilometers per second.

    For narrow frequency ranges, it is possible to slow light down to a few meters per second - if you let the light pass through that medium several times, it might be possible to get a delay of something like a few seconds. There is even stopped light, but that does not work for more than a second either. In addition, it is always frequency-specific - you do not get a regular image of an object in that way.
  4. May 22, 2013 #3
  5. May 22, 2013 #4


    Staff: Mentor

    Yea light can be slowed down to some pretty slow speeds or even trapped as a Bose Einstein Condensate. However not sure, since looking at something requires light, asking what such weird forms of light looks like is even meaningful.

  6. May 22, 2013 #5
    Thinking about it is making my brain hurt, would it just block the image when looked face on
  7. May 23, 2013 #6
    Slow light comes from an interaction between the light and the atoms of the prepared medium. Inside the medium the light is actually in a superposition of light and matter state (sometimes called polaritons). These combined light-matter particles then move much more slowly than what the light by itself would. Notice though that the light part of that combined state still works like normal light and can be absorbed by other atoms inside the medium, take part in Raman process, etc.
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