Quantum State Basis ------------------- |Ψ> = C_+ |+> + C_- |-> with |C_+|^2 + |C_-|^2 = 1 Example (pic) Spin in x, y, and z (pic) Coefficients in general |+x> = C_+ |+z> + C_- |+z> C_+ = e^(i δ_+) / √2 , C_- = e^(i δ_-) / √2 <+x| S_z |+x> = = expectation value