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Trace of an Outer Product

  1. Jun 3, 2014 #1
    Is the trace of an outer product of a normalized state eq. (psi) equal to 1?

    Chris Maness
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  3. Jun 3, 2014 #2


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    Last edited: Jun 3, 2014
  4. Jun 3, 2014 #3

    George Jones

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    It would be good for you to calculate this.

    Let ##\left\{\left| \psi_i \right>\right\}## be an orthonormal basis.


    1) express ##\left| \psi \right>## as an arbitrary linear combination of basis elements; 2) express the outer product in terms of this linear combination; 3) find the trace with respect to this basis.

    You might need a few more hints.
  5. Jun 3, 2014 #4
    I think I have it, but my LaTeX editor is giving me fits with this half bra-ket stuff. I will post it after I install MacTex on my new computer.

    That will be a while 2.2Gb later.

    Chris Maness
  6. Jun 3, 2014 #5


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    If you know the code, you can type LaTex here. We've got enabled through Mathjax.
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