I introduced the unitary transformation ##U=U_a \otimes U_b## with ##(U_a\otimes 1):\;|s,s> \rightarrow\,\frac{1}{\sqrt{d}}\sum_t \omega^{ts}|t,s> ## und ##(1\otimes U_b):\;|s,s> \rightarrow\,\frac{1}{\sqrt{d}}\sum_t \omega^{-ts}|s,t> ## ##(\omega=e^{2\pi i/d}##) and let it act on the state in...