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Homework Help: Poisson brackets, HELP!

  1. Jul 7, 2008 #1
    can anyone tell me why the poisson brackets for {x,p} = 1 ..from (dx/dx)(dp/dp) - (dx/dp)(dp/dx)... shouldn this equal 0??
     
  2. jcsd
  3. Jul 7, 2008 #2
    I don't know why you think it should be 0.

    Calculate each derivative and plug the values into the formula. You should get 1. Remember that x and p are independent.
     
  4. Jul 7, 2008 #3

    nicksauce

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    dx/dx = 1. dp/dp = 1. dx/dp = 0. dp/dx = 0. 1 - 0 = 1. Which of these is not clear to you?
     
  5. Jul 8, 2008 #4
    oh right, my lecture notes said that (dx/dp) = 1... i then assumed that (dp/dx) = 1.. oh yes and p is velocity dependent, now i get it... thanks!
     
  6. Oct 13, 2008 #5
    {x,p} = 1 therefore
    (dx/dx)(dp/dp) - (dx/dp)(dp/dx)=i
     
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