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Finite Certification of Quantum Subsystem Cuts from Unpartitioned Control Data

Oliver Tuma

Published Aug 27, 2026• 0 citations
Publisher

Abstract

Version 1.2 presents a finite sound certification procedure for operationally exposed quantum subsystem cuts without supplying subsystem labels to the factor-search stage. An exact finite control presentation with empirically confirmed interchange squares is reduced to unlabelled control-direction classes. The algorithm searches used direction subsets, forms noncommutation components, and tests the generated effect algebras for commuting matrix-factor witnesses. It distinguishes a unique finest full cut, partial factor structure with explicit residual multiplicity, and the absence of a uniquely certified cut, including ambiguity between inequivalent embedded full frames. Unused controls are localized only after certification by algebraic support. Version 1.2 closes the uniqueness proof for the global finest-frame claim, gives an exact finite tomographic characterization of terminal equality in the interchange-square condition, explicitly distinguishes the framework from Achenbach et al.'s multimeter-map factorization, fixes and reports the floating-point reference tolerance at 1e-8, and adds an independent exact 120-trial audit comparing the component reduction with exhaustive set-partition search. Five Pauli stress tests remain independently verified by tolerance-free binary-symplectic arithmetic. The operator-algebraic factorization itself is treated as standard; the priority claim remains restricted to the reverse unlabelled witness-search and certificate architecture.

DOI
10.5281/zenodo.22133053

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A finite-dimensional Hilbert space admits many inequivalent tensor-product decompositions, so exact uniqueness of subsystem structure must be formulated on a specified class of Hamiltonians and graphs. In the graph-local setting, exact zero-set identifiability means that the static selector vanishes on a single physical quotient class, or equivalently that the Hamiltonian has a unique admissible-support realization modulo local basis changes and subsystem permutation. On the deletion-robust graph class, defined by the requirement that deleting any vertex leave no isolated vertex component, the analysis gives a finite-certificate description of that question. The reference complement-generation locus in exact graph-local coefficient space is nonempty exactly on this graph class, and an explicit family of one-site fields and mixed edge couplings realizes it. Two finite certificates are then introduced on the reference exact slice: a bounded-length omitted-site word-algebra rank test and a quadratic-rigidity determinant for the first forbidden-support quadratic form. On deletion-robust graphs the resulting reference-regular locus is nonempty, Zariski-open, and Euclidean dense. Assuming the exact zero set of a base Hamiltonian is finite, each competitor exact zero determines a local branch whose intersection with the reference exact slice is governed by an explicit Jacobian-rank criterion. Near a regular-transverse base point, exact zero-set identifiability is therefore controlled by finitely many explicit obstruction manifolds. The graph boundary, the reference certificates, and the structural failure modes are all explicit within this nondegenerate exact-uniqueness framework.
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