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Group velocity in infinite square well

  1. Feb 8, 2013 #1
    ello everybody,

    how can I calculate the group velocity of a wave package in an infinite square well?

    I know only how it can be calculated with a free particle, the derivation of the dispersion relation at the expectation value of the moment.

    But in the well, there are only discrete values of k allowed.

    It would help a lot if someone could send me a link or give a little help,


  2. jcsd
  3. Feb 24, 2013 #2
  4. Feb 24, 2013 #3


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    An infinite well only allows for standing waves solutions for which it does not make sense to define group velocity.
  5. Feb 24, 2013 #4
    Dr Du.....
    Standing waves!!.....yes, I wondered about that before I posted and figured it was
    'too simple'.....actually I also figured standing waves COULD support a group velocity
    but having never studied that, dismissed the idea....
    Last edited: Feb 24, 2013
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