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Homework Help: Please help Give the following operators:

  1. Feb 18, 2008 #1
    Ive tried this quantum mechanic problem but im not getting the right anwser:

    a-operator = [x-operator + i (complex #)] (p-operator) / (square root of 2)


    a-operator ^ t = x-operator - i (p-operator) / square root of 2

    where x operator is the position operator and p operator is the momentum operator, show that [a-operator, a-operator ^ t] = h-bar or plancks constant divided by 2pi,
    or in expanded form, show that (a-operator)(a-operator ^ t) - (a-operator ^ t)(a-operator) = h-bar or plancks constant divided by 2pi
  2. jcsd
  3. Feb 18, 2008 #2


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    ok, this is homework?

    I can give you a hint. Write down the rules for the commutator, and the commutator between x and p. Notice that orders matters, [A,B] = - [B,A]

    If this is homework, then you must supply attempt to solution. This was your first post, and you should have read the forum rules https://www.physicsforums.com/showthread.php?t=149069
    Last edited: Feb 18, 2008
  4. Feb 18, 2008 #3
    hey thnx its not really hw i just said that so i could get lp faster, but its just a class assignment that IAM allowed to get solutions too, its not being graded..can you help me any further?
  5. Feb 18, 2008 #4


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    Well I can help you, but you have to supply what you have done.. we dont "work" for free here. Even though you are allowed to get solution on this one, the forum rules are clear, and I want to HELP you, not just give you the solution...

    I gave you the two things that you need, so start from there. In your textbook or lecture notes or on the internet, find the things I told you to get, then start work. Post your work here (as much as possible) if you get lost.

    I will soon be online. but some will move this thread to HW/course work forum, and answer your questions further.
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