Angular momentum theory problem probably wrong sign

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The discussion centers on proving the equality of two expressions involving angular momentum eigenkets, specifically \left\langle lm | \vec{\hat{r}} \times \vec{\hat{p}} | lm\right \rangle and \left\langle lm | \vec{\hat{p}} \times \vec{\hat{r}} | lm \right \rangle. The author attempts to express the angular momentum operator in terms of its components but finds that only the \hat{k} component remains after applying the bra-ket operation. They note that the other components cancel due to the orthogonality of the eigenkets when using ladder operators. The author suspects a sign error in the problem statement, which they believe trivializes the proof. The discussion seeks clarification and opinions on this potential issue.
lgnr
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I have to prove that \left\langle lm | \vec{\hat{r}} \times \vec{\hat{p}} | lm\right \rangle = \left\langle lm | \vec{\hat{p}} \times \vec{\hat{r}} | lm \right \rangle, where | lm \rangle are eigenkets of angular momentum operator \hat{L}^2

And I can't figure out a way to do this correctly. I wrote the angular momentum operator-vector in terms of its components, \hat{L_x}, \hat{L_y} and \hat{L_z}, and only the \hat{k} component survives the bra-ket operation, because I can write \vec{L_x} y \vec{L_y} in terms of ladder operators, and after lowering and rising the eigenstates, the corresponding eigenkets (except for the \hat{k} component) cancel with \langle lm | because of the orthogonality property of these eigenkets. Probably there is a wrong sign in the problem statement. Looks trivial in that case, but I want to know your opinion.

Thanks in advance for any advice.
 
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Undoubtedly the wrong sign.
 
Time reversal invariant Hamiltonians must satisfy ##[H,\Theta]=0## where ##\Theta## is time reversal operator. However, in some texts (for example see Many-body Quantum Theory in Condensed Matter Physics an introduction, HENRIK BRUUS and KARSTEN FLENSBERG, Corrected version: 14 January 2016, section 7.1.4) the time reversal invariant condition is introduced as ##H=H^*##. How these two conditions are identical?

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