Section III contains the
discussion of the probabilities to measure the eigenvalues of
jˆ
u[ejˆ in eigenstates of jˆ z , where e is a unit vector that
makes an angle u with ez . After presenting the general
method, we first give the explicit formulas up to j53
2. For
larger values of j the probabilities are calculated using a
simple recursion relation. Our method is conceptually much
simpler than the approach first proposed by Wigner,5 which
we present for comparison in the appendix.