Within orthodox quantum mechanics, the only empirical content of any physical claim is a change in the outcome statistics of a declared measurement. In the modern formulation of measurement theory this declaration is an instrument (a family of completely positive maps) or equivalently a POVM together with an implementation. In curved spacetimes, localized measurement theory supplies the appropriate notion of a “local interface”: a finite laboratory worldtube with finite switching, whose induced observables lie in the causal hull and whose instruments compose causally. This paper proves a closure result: for any declared localized measurement, all geometric dependence (metric, connection, curvature, horizons) can affect outcome statistics only through exactly two operational apertures: • Phase / support aperture: the implemented localized instrument or channel on the accessible algebra, including any differential proper‑time or propagation‑dependent phase and any geometry‑dependent support of the induced observable. • Entropy aperture: the accessibility restriction itself (restriction of the global state to the accessible algebra), equivalently a trace over inaccessible degrees of freedom, with the corresponding mixedness/entropy as the interface invariant. There is no third independent slot in the quantum‑mechanical probability rule into which “quantum gravity” can be inserted. Common‑mode phases are operationally null. Sub‑resolution “micro‑selection” is inadmissible without a refined POVM/instrument. And “mediator” talk without a mediator POVM is non‑identifiable, because Stinespring dilations are never unique. The closure is robust: within finite‑response classes, small perturbations of couplings or geometry produce proportionally small changes in outcome statistics. The result does not deny the possibility of new physics beyond orthodox QM. It eliminates a specific move that has repeatedly appeared in quantum‑gravity discourse: treating curvature as an additional, independently specifiable ingredient of orthodox quantum‑mechanical prediction at a local interface.
Within orthodox quantum mechanics, the only empirical content of any physical claim is a change in the outcome statistics of a declared measurement. In the modern formulation of measurement theory this declaration is an instrument (a family of completely positive maps) or equivalently a POVM together with an implementation. In curved spacetimes, localized measurement theory supplies the appropriate notion of a “local interface”: a finite laboratory worldtube with finite switching, whose induced observables lie in the causal hull and whose instruments compose causally. This paper proves a closure result: for any declared localized measurement, all geometric dependence (metric, connection, curvature, horizons) can affect outcome statistics only through exactly two operational apertures: • Phase / support aperture: the implemented localized instrument or channel on the accessible algebra, including any differential proper‑time or propagation‑dependent phase and any geometry‑dependent support of the induced observable. • Entropy aperture: the accessibility restriction itself (restriction of the global state to the accessible algebra), equivalently a trace over inaccessible degrees of freedom, with the corresponding mixedness/entropy as the interface invariant. There is no third independent slot in the quantum‑mechanical probability rule into which “quantum gravity” can be inserted. Common‑mode phases are operationally null. Sub‑resolution “micro‑selection” is inadmissible without a refined POVM/instrument. And “mediator” talk without a mediator POVM is non‑identifiable, because Stinespring dilations are never unique. The closure is robust: within finite‑response classes, small perturbations of couplings or geometry produce proportionally small changes in outcome statistics. The result does not deny the possibility of new physics beyond orthodox QM. It eliminates a specific move that has repeatedly appeared in quantum‑gravity discourse: treating curvature as an additional, independently specifiable ingredient of orthodox quantum‑mechanical prediction at a local interface.
Operational theorem package: R′ (resolution), T′ (common-mode invariance), C′ (sub-bin curvature irrelevance), D′ (near-null registrar trivialization), H′ (horizon implementability) This record contains the final manuscript and supporting materials for a strictly operational analysis of quantum measurement in spacetime. Following the introduction of Quantum Measurement Timeline Framework (QMTF), in which a measurement is defined as a POVM statement on a declared spacetime target frameD* = R* × T* at finite resolution (Δx, Δt). An event is the realization of a single POVM effect E_U on one spacetime bin U; all dynamical relations among alternatives—including gravitational influence—belong to pre-event evolution. Within this orthodox setting, we prove a five-part operational theorem package: R′ (resolution). Finite operational resolution is derived, not assumed, from the metrological chain quantum Fisher information → Bures/Fidelity → total variation distance, yielding explicit Δx_min and Δt_min at any discrimination threshold ε_disc. T′ (common-mode invariance). Uniform time dilation or global phases are probability-irrelevant for any POVM; only differential phases can affect outcome statistics. C′ (sub-bin curvature irrelevance). Curvature variations confined below the declared resolution cannot change single-bin event probabilities beyond ε_disc. After Hadamard-controlled spatial and temporal smearing, such effects are common-mode or strictly sub-threshold. D′ (near-null registrar trivialization). With finite information rate, the boundTVD ≤ √(F / 8) · τ implies that no nontrivial discrimination is possible as the registrar’s proper-time budget τ → 0. H′ (horizon implementability). An exterior laboratory cannot implement POVM effects localized strictly in the interior algebra of a black-hole spacetime; interior bins have zero operational support for exterior observers. Together, these results close “gravity at the event” in the single-run semiclassical domain: gravity can only shape pre-event phases and support via proper time and cannot appear as an event-internal degree of freedom at any finite operational resolution. Each theorem is stated with explicit inequalities and clean falsifiers (sub-resolution curvature tests, near-null discrimination limits, and exterior-only interior implementability), ensuring refutability. The framework uses no assumptions beyond standard quantum mechanics (POVMs and instruments) and general relativity (proper time and locality) and is consistent with interferometric observations such as COW neutron interferometry and Kasevich–Chu atom interferometers, where gravity appears exclusively through differential pre-event phases. Keywords: POVM measurement; operational quantum measurement; quantum Fisher information; distinguishability bounds; Unruh–DeWitt detector; Hadamard states; proper time; semiclassical quantum mechanics and general relativity; algebraic quantum field theory; interferometry, QMTF. Author: R. Necsanu ORCID: 0009‑0009‑1281‑9180 Reference record (QMTF): Necsanu (2026), Zenodo 10.5281/zenodo.18262158
This paper is the thirty-first in a sequence developing an interpretive framework that redescribes physical reality as a causally consistent history of information updates rather than as a collection of independently existing objects. It is the third panel — the capstone — of the eighth grouping, a foundational-physics trilogy. Its subject is spacetime localization: where and when a record or system is — its position, orientation, relative phase, and time. The claim is that localization is real but not authoritatively global. There is no Global Frame: no physically privileged reference system that fixes absolute location and orientation, a privileged global simultaneity, a classical frame standing outside quantum theory, and one physically privileged, globally valid perspectival gauge-fixing. Localization is relational: positions and times are defined relative to a declared quantum reference frame (QRF), itself a quantum system that may be superposed and entangled with what it localizes (Giacomini, Castro-Ruiz, & Brukner, 2019; Loveridge, Miyadera, & Busch, 2018). What keeps this objective rather than subjective is a strict typing of cross-frame comparison: a single gauge-invariant relational (Dirac) observable has one invariant prediction, its perspectival representations intertwined by a frame-change map (case A); distinct relational observables form a relationally consistent web (case B); and where two frames share no common refinement their claims are declared incomparable (case C). "Objective" means invariance of the physical predictions under the declared symmetry group and the frame-change groupoid over the admissible frame family, to a declared tolerance — never frame-independence in an absolute sense. The flagship R-A is a dynamics-independent kinematic existence witness: a finite-dimensional discrete-ring model exhibits one physical state and two admissible ideal QRFs under which the localization profile and the entanglement structure differ — a sharp product relative to one particle; an entangled state with a delocalized, mixed marginal relative to another — while the distribution of the same relational observable is preserved. R-B splits into a domain covariance on shared refinements (ideal QRFs compose and agree on shared Dirac predictions) and a model-dependent global-perspective obstruction: where a globally valid relational gauge-fixing fails, as in known Gribov-type models (Vanrietvelde, Höhn, & Giacomini, 2023), no single perspective covers the whole physical state space — which is neither the same as, nor a consequence of, the absence of a privileged frame, and does not preclude a perspective-neutral description. R-C places Paper 8's relational time as the time-translation special case, with its finite-resolution-clock, conditional-covariance, and record–clock qualifications, separating the retired claim (no global clock) from the deferred one (relativistic foliation with dynamical geometry). R-D identifies and transports the frame-representable localization sector of certain Paper-30 grains, partially discharging that paper's grain-coherence deferral while leaving interaction, fragmentation, redundancy, and history-family structure grain-relative. This completes the trilogy's dismantling of the Global Bookkeeper while keeping geometry fixed: the quantum-mechanics–gravity interface is prepared, not entered. Localization is frame-relative but objective: no absolute frame, no globally gauge-fixed perspective claimed beyond what models establish, and no anarchy. ALAC Paper 31. Third panel (capstone) of the eighth grouping — a foundational-physics trilogy (29 Public Quantum Records -> 30 Classicality Without a Global Classicalizer -> 31 Spacetime Localization Without a Global Frame). Part of the Consistency-Constrained Information History (Akashic Ledger Architecture Cosmology) series. Presents no new quantum mechanics; results are interpretive (L2) on imported physics (L1).
This work separates several physical and theoretical burdens that are often grouped together under “the quantum measurement problem” and develops an experimentally answerable test of one of them: outcome-conditioned continuation. The proposal does not treat measurement as one indivisible physical event. It distinguishes the admission of a measurement interaction and apparatus, durable record formation, later availability of that record, agreement among physical carriers, global outcome standing, quantum-probability weighting, and the rule governing what physical or predictive description continues after an outcome. These burdens can remain open or fail independently. The principal experimental proposal is the Quantum Continuation Closure Test (QCCT). QCCT-I asks whether two physically distinct proper-mixture preparation procedures that are represented by the same admitted standard quantum state can produce different later statistics after the same admitted first measurement. The canonical preparation pair consists of equal-weight Z-basis and X-basis proper mixtures that are represented by the same maximally mixed qubit density operator under standard quantum mechanics. A fixed standard quantum instrument cannot depend on which proper-mixture decomposition produced that state. Published generalized state-update rules provide explicit theory-side foils for which the preparation decomposition can instead remain relevant to the postmeasurement continuation. Ordinary quantum physics is given first refusal. Preparation mismatch, improper-mixture substitution, calibration failure, different first-measurement seats, preparation side channels, ordinary non-Lüders instruments, temporal process memory, and independently warranted expansion of the physical reference must be tested at their own declared scopes before a stronger preparation-indistinguishability violation can be inferred. QCCT therefore does not treat deviation from an ideal Lüders prediction, failure of one fitted instrument, or a preparation-dependent sequential signal as immediate evidence for new quantum dynamics. The comparison architecture escalates from fixed-instrument closure to finite-horizon process-tensor closure and only then to stronger bounded residual claims. The experiment is modular. Prospective QCCT-I execution, process-memory characterization, coarse-graining invariance, archival-data analysis, and later distributed partial closure may contribute distinct local results. A result transfers to a later experiment only through an explicit interface preserving the relevant physical carrier, reference, scope, calibration, provenance, and unresolved burdens. The deposit also contains a machine-auditable formal surface. One consolidated Lean file contains two scientifically distinct Quantum Measurement modules: Seam G, concerning Born weighting / quantum probability measure, and QCCT-I, concerning preparation-indistinguishability / outcome-conditioned continuation. Their shared file packaging does not merge their objects, burdens, evidence states, dispositions, or claims. Both generic machine dispositions remain Not Yet Adjudicable. Seam G retains open domain-owned probability-admission burdens. QCCT-I retains open empirical preparation, reference, measurement, side-channel, comparator, and adjudication burdens. The consolidated Quantum Measurement contracts-and-adapters file was appended directly beneath the unchanged Structural Flow Universal Kernel and elaborated cleanly twice during the release audit. Clean elaboration establishes only that the encoded contracts and adapters coexist coherently at their declared formal scopes. It does not derive the Born rule, establish the physical validity of the generalized continuation family, demonstrate preparation equivalence, close the ordinary quantum comparators, establish an anomaly, falsify standard quantum mechanics, or select an interpretation of quantum measurement. The physical answer remains the responsibility of experiment.
Results proved (standard QM only) (I) Resolution is forced. If the declared outcomes are coarse bins U, standard QM determines only the coarse event U. A definite sub‑bin label i ∈ U is not determined unless a refined measurement model (refined POVM and, for state update, an instrument) is specified. (II) No phase‑resource‑free DoF inflation. Fix a spatial region length L and a wavenumber bandlimit kₘₐₓ (equivalently momentum bandlimit pₘₐₓ = ħkₘₐₓ) at a declared tolerance. Then a single wavefunction cannot encode an arbitrarily finer independent spatial pattern (for example “one independent complex amplitude per microscopic site of a macroscopic screen”) without increasing the available phase/bandwidth resources. Alternatively, if one couples to genuinely many macroscopic degrees of freedom, the relevant reduced state becomes mixed under standard, explicit overlap bounds, so a single subsystem wavefunction is not licensed. Scope. This document uses only standard quantum mechanics: Hilbert‑space states, POVMs, instruments (completely positive maps / Kraus operators), classical post‑processing (coarse‑graining), and standard Fourier/sampling/operator facts. No additional premises are used.
Papers I and II derived gravitational geometry and second-order dynamics from finite accessibility without invoking measurement, observation protocols, or collapse as primitive notions. This paper extends the operational program to the measurement sector, deriving the structure of record formation and probabilistic weights from the same finite accessibility and compositional constraints. Finite accessibility restricts admissible operations on a subsystem to a proper operator subalgebra. Because bounded certification excludes operators requiring nonlocal coordination or arbitrarily fine phase resolution, the accessible algebra is strictly smaller than the full operator algebra. When a system becomes correlated with orthogonal environment sectors, off-diagonal operators between those sectors fall outside the accessible algebra. The reduced state is therefore indistinguishable, under all admissible operations, from its diagonal ensemble. Definiteness emerges as an algebraic consequence of sector restriction, not as a collapse postulate. The weights of these sectors are fixed uniquely by compositional consistency. Phase invariance, multiplicativity under independent refinement, and stability under record coarse-graining constrain any admissible assignment of sector weights to satisfy a functional equation whose only continuous, non-contextual solution is quadratic in amplitude. The Born rule therefore arises as the unique invariant measure compatible with finite accessibility. Irreversibility follows from action scaling: reversal requires operators outside the admissible tensor algebra and incurs action cost proportional to the number of correlated subsystems. Since admissible operations are bounded by the action gap, macroscopic record reversal is excluded. Measurement introduces no new physical primitives beyond finite accessibility, locality, and compositional stability. Record formation, classical definiteness, and Born probabilities are structural consequences of algebraic restriction under finite accessibility. **This paper is part of the Finite Accessibility series, which reconstructs gravitational geometry, quantum dynamics, gauge structure, cosmological perturbation theory, and the dark sector from a single operational primitive: a finite certification ceiling ω* governing the maximum rate at which physical relations can be maintained across extended domains.** **Introductory papers** - Geometric Limits to Coherent Timekeeping in Extended Reference Frames — https://doi.org/10.5281/zenodo.18824556 - Accessibility Selection Law (ASL) — https://doi.org/10.5281/zenodo.18824649 - Phase Boundary Gravity — https://doi.org/10.5281/zenodo.18824707 **Pillars (numbered I–IV)** - Paper I: Deriving Gravitational Geometry and Schrödinger Dynamics from Finite Accessibility — https://doi.org/10.5281/zenodo.18601600 - Paper II: Deriving Inertia, Motion, and Wave Propagation from Finite Accessibility — https://doi.org/10.5281/zenodo.18625174 - Paper III: Accessible State Spaces, Record Stability, and the Emergence of Quantum Statistics — https://doi.org/10.5281/zenodo.18625192 - Paper IV: Frame Dissolution, the Certification Ceiling, and Observable Deformations — https://doi.org/10.5281/zenodo.18654458 **Extension papers** - Dark Matter from Finite Accessibility — https://doi.org/10.5281/zenodo.18654433 - Dark Energy from Finite Accessibility — https://doi.org/10.5281/zenodo.18654523 - No-Go Theorems and the Admissibility Corridor — https://doi.org/10.5281/zenodo.18654493 - Gauge Structure from Finite Accessibility — https://doi.org/10.5281/zenodo.18928152 - Perturbation Theory from Finite Accessibility — https://doi.org/10.5281/zenodo.18928213 **Experimental paper** - Experimental Probes of Finite Accessibility: GW Dispersion and Vacuum Path Independence — https://doi.org/10.5281/zenodo.18931126 **Keywords:** Born rule derivation, measurement problem, quantum statistics, finite accessibility, operator subalgebra, record formation, definiteness emergence, wave function collapse, compositional consistency, accessible state spaces, action gap, irreversibility, sector restriction, quantum foundations, algebraic quantum mechanics, decoherence
Parts VIII–XI of this series reduced the program to a single missing object: a quantum measure μ(C) over causal histories. This Part XII specifies that object, realizes it in prototype, and tests whether it selects the observed effective spacetime dimension. The fundamental object is a Hermitian, positive, bi-additive Sorkin decoherence functional D(A,B) with physical measure μ(A)=D(A,A); classical measures obey the two-event sum rule I2=0, while quantum measures have I2≠0 but obey the Sorkin triple sum rule I3=0. An explicit such measure is constructed on the growth histories of small causal sets and verified numerically to satisfy I3=0 to machine precision while I2≠0. The fourth gate is sharpened beyond the standard Lorentzian-continuum requirement: the measure must concentrate on causal orders carrying coherent local proper time (a stable interval volume–proper-time law), the distinctive addition of this program. A systematic test on controlled ensembles then asks whether any non-circular intrinsic ingredient selects the 3+1 sector, with a uniformly negative result. The free measure is dominated by the entropic Kleitman–Rothschild phase (d_MM ≈ 2.37); proper-time coherence with propagation escapes that phase but settles on the effective 2+1 sector; the Benincasa–Dowker quantum phase produces only seed-unstable windows that vanish at the physically natural phase scale; and the Pauli–Jordan operator and the Sorkin–Johnston state, though intrinsic and phase-based, are monotone in dimension. A circularity audit shows that every selector whose optimum lies at four dimensions either inserts the dimension (local gravitational degrees of freedom, bound-matter stability, a (d−4)² term) or was tuned to it. The honest conclusion is that proper-time coherence explains the exit from the entropic phase but not the final 3+1 selection: the bare measure with coherence predicts an effective 2+1 phase, and the open problem is localized as the emergence of the third spatial direction (2+1 → 3+1). This yields a falsifiable prediction and identifies the missing object as a covariant, Bell-causal growth law whose continuum limit would fix the gravitational phase normalization. Supplementary Python scripts reproducing all numerical tests are included.