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Confused about Dirac notation

  1. Sep 21, 2004 #1
    So in my problem set I'm asked to solve for the "new energies of the system" I'm given the initial energies of this system and told a new potential is added. I know all the matrix elements. I solved for H|psi> so where do I go from here for the energies?
  2. jcsd
  3. Sep 21, 2004 #2
    I'm not sure, but can't you just solve H|psi> = E |psi> for the new Hamiltonian which is defined by

    H=-hbar^2/2m Laplacian +Vold+Vnew
  4. Sep 21, 2004 #3
    That's what I was thinking but I was curious if there was some other trick buried in the Dirac stuff. Thanks.
  5. Sep 22, 2004 #4

    Kane O'Donnell

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    Science Advisor

    The lecturer might be asking you to use pertubation theory - is the new potential small compared to the old?

  6. Sep 22, 2004 #5
    I think Kane is right.

    You can check wikipedia about the Dirac notation.
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