Classical and quantum 'EPR'-spin correlations in the triplet state

Quantum correlations and joint probabilities in the triplet state as well as the correlations of components of two correlated classical spin vectors, are evaluated. Correlations in the states with |Stotz|=1 are different from correlations in the state with Stotz=0 which may serve to distinguish different states of the triplet. As in the singlet case, we can reproduce quantum correlations by correlated classical spin vectors which also provide a precision of the notion of ''parallel spins''. Triplet state correlations could in principle be measured, for example, in the decay reaction J/ψ → e+e- for which there is a sufficiently large branching ratio. (author). 12 refs