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Action variables

  1. Apr 26, 2007 #1

    quasar987

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    Suppose a 1 degree of freedom system. Then, the action variable J is defined by

    [tex]J\equiv\oint p(q)dq[/tex]

    where the integral is taken over a period of p(q). What shall this period be in the case of say, an harmonic oscillator, where the path in phase-space is an ellipse and hence p(q) is not even single-valued?
     
  2. jcsd
  3. Apr 26, 2007 #2

    George Jones

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    Parametrize the ellipse in the standard way, and integrate over one period.
     
  4. Apr 26, 2007 #3

    quasar987

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    Dang it. This is what I tought about doing in my exam too but I had no more time when the idea finally hit me. Thanks GJ.
     
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