1
$\begingroup$

I know it is convention to taken Clebsch-Gordan $\color{blue}{<j_1,j_2;m_1,m_2|j_1,j_2;j,m>}$coefficients are real.If I want to make proof it's reality from any physical defination in backward then how can I do that?

$\endgroup$

1 Answer 1

2
$\begingroup$

Mmmm... I don't think there is a proof as such, since it's simply a choice of phase for the individual highest weight states $|j,j\rangle$ states in the decomposition . It would be like asking for a proof that the coefficients $\sqrt{j(j+1)-m(m-1)}$ in the action of the ladder operator $J_-$ are real. This latter reality is merely a choice of phase for the states $|j,m\rangle$ relative to that of $|j,j\rangle$.

$\endgroup$
1
  • $\begingroup$ In this case, the relevant proof would be to show that it is always possible to choose the phase so that the Clebsch-Gordan coefficients are real. $\endgroup$
    – Poseidaan
    Commented Nov 4, 2023 at 17:33

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.