Computing Wigner D-Matrices: Contradiction Found

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The forum discussion centers on computing the Wigner d-matrices, specifically d^1/2_{-1/2,1/2} and d^{1/2}_{1/2,-1/2}. According to Edmonds' equations on pages 59 and 61, both computations yield -sin(b/2), yet they should have opposite signs based on the relation d^j_{m'm}=(-1)**(m-m') d^j_{m,m'}. This discrepancy raises the possibility of a typo in Edmonds or an exception to the relation for the specific case discussed.

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I am writing a program for computing the Wigner d-matrices and ran into an apparent contradiction:

Specifically computing d^1/2_{-1/2,1/2}

According to Edmonds, p.59, 4.1.27 this is given by

(-1)**[1/2-(-1/2)][1!/(1! 0!)]**{1/2} sin(b/2)=-sin(b/2)

Now for d^{1/2}_{1/2,-1/2}
From p.61, (4.4.1) we get -sqrt(1) d^0_{00} sin (b/2)=-sin(b/2)

However, from the relation d^j_{m'm}=(-1)**(m-m') d^j_{m,m'}

these two should have the same sign as (m-m')=1/2-(-1/2)=1 is odd

Could be it a typo in Edmonds?
 
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It is possible that there is a typo in Edmonds. However, it is also possible that the relation d^j_{m'm}=(-1)**(m-m') d^j_{m,m'} does not apply for the specific case you are considering. It may be worth double checking the equation and making sure that it is valid for the case you are looking at.
 

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