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Angular momentum

  1. Sep 1, 2010 #1
    Here is the known formula for the spin: S=0.5*[STRIKE]h[/STRIKE]*[tex]\sigma[/tex]
    is this formula correct also to the orbital Angular momentum (L) and to the total Angular momentum?
    I think it is correct because S,L,J operators that belong to Lie algebra/group.
    Is it true?
  2. jcsd
  3. Sep 1, 2010 #2


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    Science Advisor

    No. The orbital angular momentum has a special form:

    {\bm L} ~=~ {\bm Q} ~\times~ {\bm P}

    where Q and P satisfy the usual Heisenberg commutation relations.
    This extra restriction causes a corresponding restriction in the
    possible eigenvalues of orbital angular momentum, namely that
    only integer values are allowed.

    Details can be found in Ballentine, pp169-170.
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