The Unreasonable Effectiveness of the Popescu-Rohrlich Correlations

In this Physics Forums Insight, I show how the Popescu-Rohrlich (PR) correlations provide an unreasonable advantage in a particular “quantum guessing game” using a pedagogical counterpart from the book “Totally Random: Why Nobody Understands Quantum Mechanics” by Tanya Bub and Jeffrey Bub (Princeton University Press, 2018). 

I show that the PR correlations are not just a little bit better than quantum correlations for the quantum guessing game, they are unreasonably effective. In fact, they violate the conservation of binary information, which translates into conservation of angular momentum on average when the information regards spin as I showed in Why the Quantum. So, it is probably the case that a physical instantiation of the PR correlations is a pipe dream akin to a perpetual motion machine.