Here is a fun talk by Fay Dowker on a path integral approach to the Greenberger-Horne-Zeilinger (GHZ) correlations. It's a physical instantiation of N. David Mermin's "no instruction sets" for GHZ in his Am. J. Phys. paper "Quantum mysteries revisited," v58, Aug 1990, 731-734. The talk is titled "Are There Premonitions in Quantum Measure Theory?" At the 39:36 mark she concludes "The physical world cannot be a single history." So, she proposes that "an interpretational scheme for path integral quantum theory -- is that the physical world is just a set of histories which is as small as it can be ... ."