Triplet versus singlet entangled states in teaching the Einstein-Podolsky-Rosen paradox

摘要

The Einstein Podolsky Rosen paradox is considered using spin-12 singlet and triplet states prepared in the 1/2-direction, after which measurements are made in a different direction, the x-direction, for example. An unexpected outcome and its usefulness for teaching is reported. The material will be of interest to upper-year undergraduate quantum mechanics instructors and students.