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Light velocity

  1. Oct 31, 2004 #1
    Light velocity....


    There is a question that I can't figure out.

    What's the difference between signal and group velocity for a light pulse ?

    What I understood so far is that the signal velocity is the velocity of the first detectable photon and the groupe velocity is the velocity of the pulse peak.

    Am I right ????
  2. jcsd
  3. Nov 1, 2004 #2
    There are definitions here :

    http://www.uni-koeln.de/~abb11/workshop/announce4.html [Broken]

    Group velocity is what it has always been : domega/dk. Signal velocity seems to be a little more delicate to define.
    Last edited by a moderator: May 1, 2017
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