🤖 AI Summary
This work addresses the systematic characterization and verification of state-independent contextuality in quantum mechanics by proposing an algebraic framework based on abelian groups. Integrating string rewriting systems with the linear-algebraic structure of the discrete Heisenberg group, the study introduces “contextual words” as algebraic witnesses of contextuality. By establishing necessary and sufficient conditions for the emergence of contextual words within abelian groups, the paper presents the first explicit construction of non-contextual value assignments and realizes a unitary representation of abelian groups within generalized Pauli groups. This approach offers a novel algebraic characterization of state-independent contextuality, combining theoretical clarity with computational tractability.
📝 Abstract
We introduce an algebraic structure for studying state-independent contextuality arguments, a key form of quantum non-classicality exemplified by the well-known Peres-Mermin magic square, and used as a source of quantum advantage. We introduce \emph{commutation groups} presented by generators and relations, and analyse them in terms of a string rewriting system. There is also a linear algebraic construction, a directed version of the Heisenberg group. We introduce \emph{contextual words} as a general form of contextuality witness. We characterise when contextual words can arise in commutation groups, and explicitly construct non-contextual value assignments in other cases. We give unitary representations of commutation groups as subgroups of generalized Pauli $n$-groups.