jfy4
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Homework Statement
Let |0,0\rangle be the simultaneous eigenstate of \mathbf{J}^2 and J_z with eigenvalues 0 and 0. Find
<br /> J_x|0,0\rangle \quad\quad J_y |0,0\rangle \quad\quad [J_x,J_y]|0,0\rangle<br />
2. The attempt at a solution
It seemed reasonable to write J_x and J_y in terms of ladder operators
<br /> J_{+}=J_x + iJ_y<br />
<br /> J_{-}=J_x -i J_y<br />
and then to have them operate on the states (for the last one I would just use the x,y,z commutation relations). But I was looking at the normalization constant out front
<br /> J_{+}|j,m\rangle = \hbar\sqrt{(j+m+1)(j-m)} |j,m+1\rangle<br />
<br /> J_{-}|j,m\rangle = \hbar \sqrt{(j-m+1)(j+m)}|j,m-1\rangle<br />
but given the initial state, these seem to be zero... Please tell me I'm doing this wrong, zero is such a unsatisfactory answer...
Thanks,