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Homework Help: How to take a complex conjugate of a 5*5 matrices?

  1. Jun 6, 2005 #1
    I'm doing a take home final and wanted reassurance that i'm doing the problem right. the question involves taking <Sz>of |psi>. I know it's
    <psi|Sz|psi>. I've never done it for a spin 2 particle which is a 5*5 matrix.Do i just take the complex conjugate of the values without switching their position within the matrices.
  2. jcsd
  3. Jun 7, 2005 #2
    Ok, I don't really know what your notation means, but for any matrix, yeah, you just replace each element with its complex conjugate.
  4. Jun 7, 2005 #3


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    "<psi|Sz|psi>" is not a 5*5 matrix,is just a number=matrix 1*1.If you mean

    [tex] \langle\psi_{i}|\hat{S}_{z}|\psi_{j}\rangle \ , \ i,j=\overline{1,5} [/tex]

    ,then yes,it's a complex matrix;unless [itex] |\psi_{i}\rangle [/itex] are eigenvectors of the selfadjoint operator [itex] \hat{S}_{z} [/itex],the entries in the matrix are complex #-s with nonzero imaginary part.

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