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arXiv:2610.00357

Hidden-State Updates and observable-record composition in retrocausal models

D. M. Theshan N. Weerasinghe

quant-phSubmitted Sep 30, 2026• Announced Oct 1, 2026• 0 citations
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Abstract

A hidden-variable model can reproduce context-independent individual readouts while failing to preserve observable records when devices are connected or reused. We distinguish two composition requirements. For a finite family of nonnegative instrument matrices, an invariant space generated by normalization defects characterizes unit continuation mass under every finite adaptive policy. Its annihilator defines the maximal admissible positive cone closed under outcome-conditioned updates. A separate observation space characterizes indistinguishability of context-dependent hidden preparations under joint readout. A finite-state example passes every fixed sequence but fails under outcome-dependent stopping. For a wrapped-Cauchy spin source with an explicitly stipulated unchanged-source passive extension, two individually fair probes acquire a setting-dependent agreement probability with contrast $ε^2\operatorname{sech}(2g)/4$. More generally, protection under one and two identical uses forces a continuous binary passive response to be constant; measurable two-valued exceptions remain possible. Exact rational calculations, exhaustive finite-policy experiments, continuous source sampling, and quadrature test the stated examples. The criteria apply to specified instrument families and accessible records; they do not construct a microscopic detector or establish consistency under unrestricted network composition.

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Detector outcome probabilities can be independent of a later measurement setting even when earlier timestamps, detector seeds, or environmental records depend on that setting. We characterize complete-record preservation for a positive wrapped-Cauchy retrocausal spin source. An antipodal identity yields necessary and sufficient conditions for passive and environmental readouts, and source compensation permits a common normalized analyzer for source spins and prepared continuations. Gaussian controller and reset calculations distinguish inverse raw history weights from normalized thermal operations. A quantum instrument provides an operational benchmark, whereas a setting-dependent separable source produces setting-dependent statistics at an earlier joint probe. For two equal-width contexts, a calibrated weak probe requires a minimum source change of $\operatorname{sech}(2g)/8$ in trace distance for exact protection at every nonzero strength. The signal--source-change tradeoff is sharp for this pair of contexts. A contextual positive-history construction recovers the isolated hidden law and preserves records for a specified class of finite adaptive quantum apparatuses, subject to quantum calibration and restricted field access. Direct readout of an added likelihood field distinguishes two future axes with unit probability. The analytical results are supported by continuous-angle and quantum-trajectory simulations, deterministic quadrature, and exhaustive enumeration of a finite policy class. The analysis concerns the specified statistical models; their microscopic physical realization remains an open question.

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Quantum Measurement: Separating the Physical Burdens and Testing Outcome-Conditioned Continuation

Rick - PraxisFoundry001

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•Sep 21, 2026•1 citation
A hidden-variable model can reproduce context-independent individual readouts while failing to preserve observable records when devices are connected or reused. We distinguish two composition requirements. For a finite family of nonnegative instrument matrices, an invariant space generated by normalization defects characterizes unit continuation mass under every finite adaptive policy. Its annihilator defines the maximal admissible positive cone closed under outcome-conditioned updates. A separate observation space characterizes indistinguishability of context-dependent hidden preparations under joint readout. A finite-state example passes every fixed sequence but fails under outcome-dependent stopping. For a wrapped-Cauchy spin source with an explicitly stipulated unchanged-source passive extension, two individually fair probes acquire a setting-dependent agreement probability with contrast ε2sech⁡(2g)/4ε^2\operatorname{sech}(2g)/4ε2sech(2g)/4. More generally, protection under one and two identical uses forces a continuous binary passive response to be constant; measurable two-valued exceptions remain possible. Exact rational calculations, exhaustive finite-policy experiments, continuous source sampling, and quadrature test the stated examples. The criteria apply to specified instrument families and accessible records; they do not construct a microscopic detector or establish consistency under unrestricted network composition.
Detector outcome probabilities can be independent of a later measurement setting even when earlier timestamps, detector seeds, or environmental records depend on that setting. We characterize complete-record preservation for a positive wrapped-Cauchy retrocausal spin source. An antipodal identity yields necessary and sufficient conditions for passive and environmental readouts, and source compensation permits a common normalized analyzer for source spins and prepared continuations. Gaussian controller and reset calculations distinguish inverse raw history weights from normalized thermal operations. A quantum instrument provides an operational benchmark, whereas a setting-dependent separable source produces setting-dependent statistics at an earlier joint probe. For two equal-width contexts, a calibrated weak probe requires a minimum source change of sech⁡(2g)/8\operatorname{sech}(2g)/8sech(2g)/8 in trace distance for exact protection at every nonzero strength. The signal--source-change tradeoff is sharp for this pair of contexts. A contextual positive-history construction recovers the isolated hidden law and preserves records for a specified class of finite adaptive quantum apparatuses, subject to quantum calibration and restricted field access. Direct readout of an added likelihood field distinguishes two future axes with unit probability. The analytical results are supported by continuous-angle and quantum-trajectory simulations, deterministic quadrature, and exhaustive enumeration of a finite policy class. The analysis concerns the specified statistical models; their microscopic physical realization remains an open question.
No-signalling constraints on isolated outcome probabilities do not determine whether an apparatus preserves the joint law of its accessible records under repeated readout, network composition, or reuse. We study these extensions through a conditional-record criterion and four explicit models. For a wrapped-Cauchy retrocausal source, protection under two conditionally independent continuous readouts forces an angle-independent response; three readouts suffice without continuity. A finite angular-bandwidth assumption gives a quantitative leakage bound, whereas continuity alone gives no uniform stability. At a specified two-source Bell junction, the required correction matrix has full nonnegative rank on every even uniform angular grid. A Gaussian controller can cancel branch-mass dependence while leaving a distinguishable joint record, for which we derive exact noise and law-change tradeoffs. Finally, a fixed singlet with shared classical noise reproduces the variable-width isolated outcome family, but retained and refreshed controllers generate different temporal statistics. We prove a finite-resource obstruction and construct positive finite-controller approximations. Numerical studies comprising 8.3 million independent simulated histories support the model-specific predictions. Together, the results identify conditions that must accompany marginal no-signalling when extending an apparatus to richer records and interventions.
Adaptive measurements test whether a retrocausal model preserves observable records when experiments are connected by classical feedback. We establish exact and quantitative composition constraints for a finite-width, coplanar Schulman-type source with positive wrapped-Cauchy propagation weights. Raw segment composition admits an explicit adaptive signalling witness. A uniquely determined scalar correction preserves recorded continuations, and a detector with preparation memory implements this correction while retaining the source correlations. For common, independently prepared terminal detectors coupled to the source through arrival angles, exact calibration forces equal-mass antipodal atomic responses. Under setting-only raw feedback, the sharp minimum worst disturbance of an earlier record is ε⋆(0)=[2cosh⁡(2Γ)]−1ε_\star(0)=[2\cosh(2Γ)]^{-1}ε⋆​(0)=[2cosh(2Γ)]−1, where ΓΓΓ is the total source-path width. We derive explicit finite-error bounds and prove linear small-error improvement. For four settings at Γ=0.4Γ=0.4Γ=0.4, a uniform reduction over arbitrary nonnegative response measures and a continuous polynomial certificate establish ε⋆(δ)=ε⋆(0)−C0.4δ+O(δ2)ε_\star(δ)=ε_\star(0)-C_{0.4}δ+O(δ^2)ε⋆​(δ)=ε⋆​(0)−C0.4​δ+O(δ2), with C0.4≃9.351091771057010C_{0.4}\simeq9.351091771057010C0.4​≃9.351091771057010. A positive five-atom detector attains this coefficient. The results quantify the compatibility of isolated-source accuracy and adaptive record preservation, and provide precise design conditions for retrocausal apparatus models with explicit preparation, memory, and control.
We develop a mathematical account of how continuous state spaces can support discrete admissible modes, dynamically distinguished outcomes, and finite records. The observer is formulated as a context-dependent composition of preparation or constraint, evolution, and readout. Coherence compression is tied to preservation of specified observables and responses. Within this formulation, we prove conditional results for discrete basin quotients and finite registration, and examine a boundary-value example with isolated mode parameters. A continuous quantum pointer then provides an explicit recording model: its interaction can encode source-sector information into distinguishable pointer states while the position observable retains a continuous spectrum. Exact records at a designated time are possible under a specified preparation; robustness and duration of storage require additional conditions. These results establish precise ways in which discreteness can occur within a continuous model. They also identify obstructions: continuity prevents a nonconstant map from a connected domain into a discrete space, compression need not have a discrete codomain, and probabilities over records do not by themselves select a single outcome. The universal observer is developed as a proposed organizing principle whose physical scope remains to be established. We distinguish demonstrated statements, conditional deductions, candidate structures, and ontological interpretation, while retaining the research question of how closure and nonclosure can belong to a common coherent structure. Keywords: universal observer; coherence compression; continuum; discrete quotient; spectral admissibility; recording; sectorization.
The same position need not imply the same future: observing an address may discard information about past events, active memory, and records. This work determines the data needed to reconstruct a temporal law and reconcile its spatial, coherent, and record readouts. Admissible extensions of a history define a graded generator of actualization; marked event rates specify its dynamics in physical time. We establish separate criteria for recovering the event count from an address and for the predictive sufficiency of that address. A distinguishing future test yields a sharp lower bound on the error of a purely spatial description. On a finite strongly connected state space, marked cycle probabilities classify strictly positive laws up to local changes of clock. For factorized first-event records, outcome fractions form a complete metric invariant after a common reparametrization of age has been factored out. On a finite irreducible state space, zero configurational entropy production characterizes the unitary continuation of the same temporal form. Its invariant complex sectors realize all finite-dimensional autonomous Hamiltonian dynamics, up to a global phase. Preparation, probabilistic readout, and retention of a sector require separate operational conditions. The zero-support condition for address jumps acquires the precise meaning of preserving the admissible state space, provided that the continuous evolution is also checked. For a phase-pure QND writer, an independently calibrated rate of record discrimination predicts transition suppression and a sufficient event-count budget on a finite interval. The joint pressure of transport and recording distinguishes realizations with identical separate marginals. Marked irreversibility may persist even when the configurational dynamics is reversible. These results define a testable sequence: reconstruct the event law, determine its sufficient readouts, and compare predictions across instruments. Equilibrium event algebras, protected phase constructions, and local clocks for infinite systems extend this sequence under explicitly stated assumptions. This preprint develops the temporal sector of the Theory of Structural Articulation (TSA).
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.