# Question about angular momentum and spin

1. Feb 17, 2009

### rabbit44

Hi quick question, is there a reason that the eigenvalues of Jz, Lz and Sz are all denoted m? Are they the same? Because I have seen them interchanged such as in addition of angular momenta.

Thanks

2. Feb 17, 2009

### malawi_glenn

One call them M since they was found experimentally by interaction by EM-fields, "Magnetic Quantum Number" :-)

One should use subscript in order to differ between them:

$$m_j, \, m_s, \, m_\ell$$