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QM - Spin operator conjugate question

  1. Nov 5, 2011 #1
    1. The problem statement, all variables and given/known data

    Okay so I've got a question I really need answered first up! If I have a 2x1 matrix for Psi, is Psi* a 1x2 matrix with all the 'i's turned to '-i's?

    Now onto the actual question - http://imgur.com/3ucb4" [Broken] - part b only

    2. Relevant equations

    http://imgur.com/bcEm3" [Broken]

    (Sorry to URL everything)

    3. The attempt at a solution

    http://imgur.com/FW0dP" [Broken]

    What did I do wrong?
    Last edited by a moderator: May 5, 2017
  2. jcsd
  3. Nov 5, 2011 #2
    Simply have the 2 x 2 matrix of Sx operate on the state v, then multiply your new 2 x 2 matrix with the conjugate of v.

    And yes the conjugate of v is a transpose matrix with the i's all different.
  4. Nov 5, 2011 #3
    Isn't that what I did? v is a 2x1 matrix. When I multiply Sx with v I'm left with a 2x1 matrix, not a 2x2.

    Sx times v = v

    v* times v = 2

    Integral = infinity
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