Noncontextual coloring of orthogonality hypergraphs

TL;DR

This paper explores the coloring and representation of orthogonality hypergraphs, linking classical truth assignments with quantum contextuality, and discusses reconstruction and coloring limitations in specific hypergraph classes.

Contribution

It introduces methods for coloring orthogonality hypergraphs using minimal two-valued states and analyzes the reconstructability and coloring constraints in various hypergraph categories.

Findings

Reconstruction is feasible for perfectly separable hypergraphs.

Colorings can be derived from a minimal set of two-valued states.

Some hypergraphs cannot be reconstructed or have coloring properties that differ from their maximal clique number.

Abstract

We discuss representations and colorings of orthogonality hypergraphs in terms of their two-valued states interpretable as classical truth assignments. Such hypergraphs, if they allow for a faithful orthogonal representation, have quantum mechanical realizations in terms of intertwined contexts or maximal observables that are widely discussed as empirically testable criteria for contextuality. Reconstruction is possible for the class of perfectly separable hypergraphs. Colorings can be constructed from a minimal set of two-valued states. Some examples from exempt categories are presented that either cannot be reconstructed by two-valued states or whose two-valued states cannot yield a chromatic number that is equal to the maximal clique number.