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Energy travels at group velocity and not phase velocity?

  1. Jun 17, 2014 #1
    How to prove that energy travels at group velocity and not phase velocity?
  2. jcsd
  3. Jun 17, 2014 #2


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    Start here: http://en.wikipedia.org/wiki/Group_velocity

    Note that the group velocity is not always the speed for energy transfer!

    A general proof is given in this paper: http://journals.aps.org/archive/abstract/10.1103/PhysRev.105.1129 [Broken]
    "General Theorems on the Equivalence of Group Velocity and Energy Transport"
    Last edited by a moderator: May 6, 2017
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