Microscopic analogs of the Greenberger-Horne-Zeilinger experiment

Abstract

This paper shows how analogs of the Greenberger-Horne-Zeilinger experiment, which demonstrates the impossibility of certain types of local hidden-variable theories in quantum mechanics, can be performed using nuclear magnetic resonance on spins in molecules at finite temperature. Because of their microscopic nature, these experiments cannot rule out the presence of nonstandard interactions that could cause classical variables to imitate quantum variables. Instead, they are designed to reveal the peculiarly quantum-mechanical correlations on which the Greenberger-Horne-Zeilinger effect is based.