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Could this be true?

  1. May 11, 2005 #1
    In an article which I had read last year about a couple of scientists slowing the speed of light to almost 38mph by reaching almost Absloute zero.

    since the speed of light in a vacume is the maximum universal speed limit, would this mean that 38mph is the minimal universal speed limit?

    if this Idea is wrong can someone please give reasons why it is wrong so I can understand and hopefuly learn from my mistakes :smile:


    Oh incase anyone wants to read the article here is a link

    http://www.news.harvard.edu/gazette/1999/02.18/light.html
     
  2. jcsd
  3. May 11, 2005 #2
    Well its wrong because I know about a million things that go slower than 38 mph, as to why its wrong I'm sure you will get better answers from someone else. But it's not just the super cold temperature that makes the light slow down by itself for starters.
     
    Last edited: May 11, 2005
  4. May 11, 2005 #3

    ZapperZ

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    You are several years too late. The same group headed by Lena Hau has managed to "halt" light completely, i.e. 0 m/s.[1] So there is no "minimal unversal speed limit", at least not from this.

    Zz

    [1] C. Liu et al., Nature v.409, p.490 (2001).
     
  5. May 11, 2005 #4
    Would 38mph have been the 'maximum universal speed limit' in the ~0K conditions? For those of us who don't have access to journals, can you summarize the experiment?
     
  6. May 11, 2005 #5

    ZapperZ

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    This report should answer your question.

    http://physicsweb.org/articles/world/14/9/8/1

    Zz.
     
  7. May 11, 2005 #6
    I thought the photon was fundamental? How can there be 1/400th of a photon?
     
  8. May 11, 2005 #7

    ZapperZ

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    It's 1/400th of 25,000 free-space photons!

    Zz.
     
  9. May 11, 2005 #8
    Am I misunderstanding or did they make a critical grammatical error?
     
  10. May 12, 2005 #9
    seems like I am several years back :) hah. had not read about them being able to stop it.
     
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