The invention relates to calibration, validation, and control of a quantum system, such as a quantum processor, a quantum sensor, or a quantum measurement apparatus. More particularly, the invention provides a computer-implemented method and system for determining whether a phase-offset and/or phase-lag indicator derived from at least two observation streams is sufficiently identifiable for use in inference and/or parameter update. Rather than permitting direct use of the indicator once computed, the invention requires passage of a machine-enforceable identifiability gate Iφ before the indicator is admitted for downstream use. In preferred implementations, the method defines at least a first measurement role and a second measurement role, acquires observation data under the two roles according to a role-activation schedule that prevents simultaneous access within the same acquisition step, and computes at least one phase-offset/phase-lag indicator over a candidate lag window. The identifiability gate Iφ then applies multiple technical checks, including calibration or estimation of acquisition-chain latency, instrument swap and/or acquisition-chain swap to test invariance of the indicator, at least one negative control, and explicit failure criteria for declaring the indicator not identifiable. Only when the indicator passes the gate is it used to generate a validated output and to update at least one control, acquisition, or signal pre-processing parameter of the quantum system. Upon failure of the gate, any parameter update based on the indicator is blocked and diagnostic data are output. In more specific embodiments, role switching is accepted only when predefined micro-invariants Q are preserved within tolerance, and a Van-proxy role-switch action is selected only if it passes a Van-proxy audit configured to reject actions that perturb relevant micro-dynamics of the quantum system. Additional embodiments may employ an adaptive role-activation schedule, a macro-entropy-based drift or instability signal, a frozen configuration manifest with version-specific hash binding, and a parameter-update lock that remains active until a new identifiability cycle passes after drift or failure. The invention thereby reduces artifact-driven parameter updates, improves robustness against acquisition-chain asymmetry and processing artifacts, and provides controlled requalification before re-enabling update.
The invention relates to calibration, validation, and control of a quantum system, such as a quantum processor, a quantum sensor, or a quantum measurement apparatus. More particularly, the invention provides a computer-implemented method and system for determining whether a phase-offset and/or phase-lag indicator derived from at least two observation streams is sufficiently identifiable for use in inference and/or parameter update. Rather than permitting direct use of the indicator once computed, the invention requires passage of a machine-enforceable identifiability gate Iφ before the indicator is admitted for downstream use. In preferred implementations, the method defines at least a first measurement role and a second measurement role, acquires observation data under the two roles according to a role-activation schedule that prevents simultaneous access within the same acquisition step, and computes at least one phase-offset/phase-lag indicator over a candidate lag window. The identifiability gate Iφ then applies multiple technical checks, including calibration or estimation of acquisition-chain latency, instrument swap and/or acquisition-chain swap to test invariance of the indicator, at least one negative control, and explicit failure criteria for declaring the indicator not identifiable. Only when the indicator passes the gate is it used to generate a validated output and to update at least one control, acquisition, or signal pre-processing parameter of the quantum system. Upon failure of the gate, any parameter update based on the indicator is blocked and diagnostic data are output. In more specific embodiments, role switching is accepted only when predefined micro-invariants Q are preserved within tolerance, and a Van-proxy role-switch action is selected only if it passes a Van-proxy audit configured to reject actions that perturb relevant micro-dynamics of the quantum system. Additional embodiments may employ an adaptive role-activation schedule, a macro-entropy-based drift or instability signal, a frozen configuration manifest with version-specific hash binding, and a parameter-update lock that remains active until a new identifiability cycle passes after drift or failure. The invention thereby reduces artifact-driven parameter updates, improves robustness against acquisition-chain asymmetry and processing artifacts, and provides controlled requalification before re-enabling update.
In some embodiments, disclosed systems and methods provide resource-aware scheduling of quantum error-correction (QEC) stabilizer measurements at a resource-constrained stage. A classical controller obtains stage state data indicative of resource availability and, for each control interval, determines a measurement execution policy constrained by the stage state data (in some embodiments, comprising a measurement schedule and/or per-stabilizer execution rates or probabilities). The controller computes one or more observability-risk indicators that quantify accumulated loss of observability (or a quantitative proxy thereof), mismatch between a predictive model and observed syndrome data, and/or uncertainty of a decoder or estimator output. An observability guard enforces bounded observability by causing a full-observation operation when elapsed time since a most recent full-observation operation reaches a threshold T_max and/or when drift or elevated risk is detected, and may do so even when a controller-layer resource guard would otherwise restrict execution due to reduced resource availability, while remaining subject to an independent physical safety interlock or absolute cutoff external to the controller, when provided. In some embodiments, the resource constraint is implemented using a resource model and a time-varying resource headroom value R(t) with predicted constrained-resource consumption constrained by R(t). In some embodiments, the resource constraint is implemented using a resource-availability indicator derived directly from stage state data and reactive adaptation without requiring prediction. In some embodiments, the resource-availability indicator is derived from a computed headroom value R(t), for example as a thresholded or quantized headroom class of R(t). In some embodiments, a dual-budget formulation tracks both resource-budget state and observability-risk budget state (e.g., resource tokens and QEC-risk tokens), optionally using a sentinel subset to maintain drift visibility and to update an error/noise model under constrained resources. In a non-limiting cryogenic embodiment, stage state data comprises cryogenic state data, R(t)=H(t) comprises cooling headroom, and resource-budget state may be represented using thermal tokens.In some embodiments, the observability-risk indicator comprises a model uncertainty measure.In some embodiments, the observability guard initiates the full-observation operation according to a predetermined or randomized refresh schedule that is independent of the stage state data and independent of the resource-availability indicator, while still being subject to any independent physical safety interlock or absolute cutoff external to the classical controller, when provided.In some embodiments, the observability guard initiates the full-observation operation based on a stochastic refresh mechanism in which inter-refresh intervals are drawn from a configured probability distribution and/or are generated by a pseudorandom process, without requiring a comparison of elapsed time to a fixed threshold. In some cases, the configured probability distribution has at least one parameter that is configurable based on a drift metric and/or the observability-risk indicator.In some embodiments, the system optionally includes an independent physical safety interlock or absolute cutoff external to the classical controller; when provided, initiation and/or execution of the full-observation operation is conditioned on the interlock or cutoff, and when not provided the observability guard may initiate the full-observation operation without such conditioning.In some embodiments, non-limiting method overview (example steps): (i) obtain stage state data; (ii) derive a resource constraint from the stage state data, including by computing resource headroom R(t) using a resource model or by deriving a resource-availability indicator without using a resource model; (iii) determine or update a measurement execution policy for a control interval subject to the resource constraint; (iv) compute one or more observability-risk indicators; (v) evaluate observability-guard conditions, including a time-based threshold T_max and/or drift/risk criteria; (vi) execute stabilizer measurements according to the measurement execution policy, optionally including a sentinel subset; (vii) when triggered, execute a full-observation operation, including as a multi-interval refresh sequence; (viii) compute deviation and/or drift metrics; (ix) update an error/noise model and optionally resource-model parameters and/or budget state; and (x) repeat for subsequent control intervals.
An improved method of distributing timing information is provided. The method includes transmitting encrypted timing signals from two or more beacons at different locations. The encrypted timing signals are transmitted at regular intervals and are received by a receiver. The receiver then performs a logic operation on the encrypted timing signals and validates, based on the logic operation, the authenticity of the timing signals. The logic operation also results in a decrypted message from the beacons, which can contain additional information, for example, data to be sent back to the beacons to verify receipt.
Can an attacker turn influence over an artificial intelligence (AI) adviser into a harmful quantum error-correction update? We identify an ambiguity in passive syndrome records that obstructs recovery selection, then show how additional calibration measurements support certified recovery updates under uncertainty and drift. In an odd-distance square toric code with error-free preparation, syndrome measurements, and recovery operations, opposite coherent X rotations produce identical passive syndrome-history distributions. Yet a fixed phase correction can help at one sign and harm at the other. A terminal logical measurement on known encoded calibration states supplies the missing sign information. A separate evaluator accepts an update only when calibration uncertainty and a justified drift bound certify improvement over the current recovery, without assuming that the adviser recommends correctly. In simulated advice attacks, calibration-confidence checks reject harmful proposals while retaining beneficial updates under honest advice. We derive sufficient limits on calibration age that require improvement through deployment. In matched simulations, a validated channel-specific bound retains more beneficial updates than the general bound after accounting for evaluation time, while preventing the tested harmful activations under the stated drift assumption. A separate surface-code experiment includes stochastic circuit faults and noise changing during acquisition. Deterministic controllers achieve at least as many beneficial updates with the same observations. Violating the drift assumption permits harmful acceptance in the toric experiment. The results identify information required for recovery selection, establish conditional guarantees against harmful updates, and quantify the recovery improvements forgone through conservative acceptance.
Described herein are various technologies pertaining to detecting tampering of a seal based upon quantum optical communication via a communications channel comprising the seal. A plurality of pulses of light encoded with random data are transmitted on the communications channel, whereupon they are received and their data values measured. The measured data values of the pulses are then compared to the known transmitted data to determine a correlation statistic between the transmitted and received data values. Tampering with the seal can be detected based upon identifying that the correlation statistic has dropped below a threshold non-tampered level of correlation between transmitted and received values.
HLV-DS-SPEC-001R Implementation Freeze v0.1.0 freezes the deterministic executable recovery implementation for the prospective HLV-DS-SPEC-001R carrier spectral-specificity test. The controlling recovery protocol is: Krūger, M. (2026). HLV-DS-SPEC-001R: Prospective Recovery of the Native 6D-to-3D Carrier Spectral-Specificity Gate After Q-Control Capacity Stop — Pre-Execution Protocol Freeze v0.1.0. Zenodo. DOI: 10.5281/zenodo.22162097. The recovery protocol follows the first locked HLV-DS-SPEC-001 execution, archived at DOI 10.5281/zenodo.22161966, which terminated with the frozen machine verdict: DSSPEC001_INCONCLUSIVE_CONTROL_CAPACITY_OR_NUMERICAL because the Q-control generator produced only 15 of the required 31 structurally admissible controls within the original frozen ceiling of 512 candidate seeds. The parent run stopped under the frozen feature firewall before any target/control QSPEC or RRESP spectral signature, target-control distance, spectral-band gate, family score, or overall spectral-specificity PASS/FAIL was evaluated. The sole load-bearing recovery change implemented in HLV-DS-SPEC-001R is: Q candidate-search ceiling: 512 -> 4096. The Q generator itself, deterministic candidate ordering, structural acceptance rules, source-cell capacity matching, connectedness requirement, target carrier, graph Laplacian, spectral normalization, QSPEC and RRESP definitions, null families, control counts, scoring rules, leave-one-out procedure, margin threshold, spectral-band rule, numerical audits, feature firewall, W and IRR capacity rules, and physical claim boundaries remain unchanged. A mandatory continuity gate is implemented before the extended Q search is permitted. The recovery engine must reproduce the complete archived 31-control R family and the exact sequence of 15 archived Q controls obtained from the original candidate prefix 0..511. The archived sparse incidence matrices are compared structurally before any Q candidate with offset >= 512 may be accepted. No target or control spectrum is computed during this continuity gate. Only if the continuity gate passes may the Q candidate sequence continue prospectively through offsets 512..4095 until either the first 31 admissible Q controls have been obtained or the frozen 4096-candidate ceiling is exhausted. As in the parent implementation, the complete structurally accepted R/Q/W/IRR control bank must be generated, written, canonicalized, and SHA-256 hash-fixed before any target or control QSPEC/RRESP calculation is permitted. The implementation retains the parent finite-carrier spectral definitions: L0 = B1 B1^T with scale-quotiented active eigenvalues, a 64-component QSPEC empirical quantile signature, and a 129-component dimensionless Lorentzian-regularized RRESP signature with fixed gamma = 1/64. The confirmatory decision rules remain unchanged. For each null family and each signature, the target distance must exceed the strict maximum leave-one-out control distance, satisfy the frozen margin threshold >= 1.50, and exceed the corresponding maximum leave-one-out distance in at least two of three prospectively defined spectral sub-bands. A family passes only if both QSPEC and RRESP pass, and overall PASS requires all four R/Q/W/IRR families to pass. This implementation freeze was prepared and technically validated before any HLV-DS-SPEC-001R scientific target/control spectral execution. Validation was restricted to implementation-level checks including syntax/compile tests, synthetic graph-spectrum tests, independent QSPEC/RRESP formula checks, scorer tests, R-rewiring checks, capacity-matching checks, IRR basis-alignment checks, package-integrity verification, and synthetic sparse-matrix continuity-comparator tests. No HLV-DS-SPEC-001R target/control spectrum, QSPEC/RRESP distance, family score, sub-band result, or scientific machine verdict was computed or inspected during preparation of this implementation freeze. The package contains the deterministic recovery engine, the exact One-Click Locked Colab notebook, machine-readable implementation specification, controlling recovery protocol, parent implementation archive, parent locked inconclusive result archive, locked DG-001 target archive, source provenance, technical validation materials, and SHA-256 manifests. After public archival of this exact implementation freeze, the next permitted action is one unchanged execution of the frozen One-Click Colab. A later PASS would establish only finite scale-quotiented graph-spectral specificity of the frozen carrier against the declared R/Q/W/IRR null ensemble. It would not establish dark matter, physical extra dimensions, Kaluza-Klein states, dark photons, particles, an absolute mass or energy scale, stress-energy, electromagnetic invisibility, gravity, halo dynamics, cosmology, or observational validation. A later FAIL would reject only the tested graph-spectral specificity route under the frozen null ensemble. Controlling provenance: Corrected parent protocol: DOI 10.5281/zenodo.22160655 Parent implementation freeze: DOI 10.5281/zenodo.22161422 Parent locked inconclusive result: DOI 10.5281/zenodo.22161966 Recovery protocol freeze: DOI 10.5281/zenodo.22162097
Quantum communication transmitters include beacon lasers that transmit a beacon optical signal in a predetermined state of polarization such as one of the states of polarization of a quantum communication basis. Changes in the beacon polarization are detected at a receiver, and a retarder is adjusted so that the states of polarization in a received quantum communication optical signal are matched to basis polarizations. The beacon and QC signals can be at different wavelengths so that the beacon does not interfere with detection and decoding of the QC optical signal.