A companion paper reported a fail-closed estimator — the Quantum Control Kernel (QCK) — that detects the precursor of systematic bias drift in cryogenic quantum control before actuator saturation, validated in simulation and against live, publicly accessible IBM hardware-calibration data. This paper reports what the estimator is for: the Quantum Control Architecture (QCA), a governed measurement-and-control layer in which the demonstrated kernel is the sensing floor of a larger construction. The construction is not free design. It is the quantum instantiation of a result established generically in the Finite Cognition series: a finite observer serving both a committing execution demand and a wide-field vigilance demand is forced to partition the two and re-couple them at the point of finalisation, so that no output is committed that vigilance has not verified. We show that quantum control information forces exactly this construction — telemetry is consumed by every layer of the control stack yet governed by none of them; observation of a quantum plant must be non-perturbative by discipline, not by hope; and an estimator that is fluent but ungoverned reproduces, on the control substrate, the same confident-and-blind failure the series identified generically. We then state the architecture that discharges the constraint, in its public units: a non-perturbative observer (NPO); the QCK detection floor; fail-closed gates that allow, abstain, or refuse; a state-coherence and equilibrium discipline over commits; provenance-checked memory that refuses known-failure patterns; a lifecycle and loop supervisor; a measurement plane of stability, coupling, margin, and cost features; and an integrity plane that audits the architecture’s own calibration model and gates its portability to new hardware on provably leak-free relocation. We are explicit about maturity throughout: the kernel is demonstrated at Technology Readiness Level 4 under published bounds; the architecture beyond it is compile-ready geometry — derived, specified, and internally consistent, not validated as live middleware on partner hardware. The architecture is advisory by construction: the operator owns the plant at every depth.
A companion paper reported a fail-closed estimator — the Quantum Control Kernel (QCK) — that detects the precursor of systematic bias drift in cryogenic quantum control before actuator saturation, validated in simulation and against live, publicly accessible IBM hardware-calibration data. This paper reports what the estimator is for: the Quantum Control Architecture (QCA), a governed measurement-and-control layer in which the demonstrated kernel is the sensing floor of a larger construction. The construction is not free design. It is the quantum instantiation of a result established generically in the Finite Cognition series: a finite observer serving both a committing execution demand and a wide-field vigilance demand is forced to partition the two and re-couple them at the point of finalisation, so that no output is committed that vigilance has not verified. We show that quantum control information forces exactly this construction — telemetry is consumed by every layer of the control stack yet governed by none of them; observation of a quantum plant must be non-perturbative by discipline, not by hope; and an estimator that is fluent but ungoverned reproduces, on the control substrate, the same confident-and-blind failure the series identified generically. We then state the architecture that discharges the constraint, in its public units: a non-perturbative observer (NPO); the QCK detection floor; fail-closed gates that allow, abstain, or refuse; a state-coherence and equilibrium discipline over commits; provenance-checked memory that refuses known-failure patterns; a lifecycle and loop supervisor; a measurement plane of stability, coupling, margin, and cost features; and an integrity plane that audits the architecture’s own calibration model and gates its portability to new hardware on provably leak-free relocation. We are explicit about maturity throughout: the kernel is demonstrated at Technology Readiness Level 4 under published bounds; the architecture beyond it is compile-ready geometry — derived, specified, and internally consistent, not validated as live middleware on partner hardware. The architecture is advisory by construction: the operator owns the plant at every depth.
A companion paper reported a fail-closed estimator — the Quantum Control Kernel (QCK) — that detects the precursor of systematic bias drift in cryogenic quantum control before actuator saturation, validated in simulation and against live, publicly accessible IBM hardware-calibration data. This paper reports what the estimator is for: the Quantum Control Architecture (QCA), a governed measurement-and-control layer in which the demonstrated kernel is the sensing floor of a larger construction. The construction is not free design. It is the quantum instantiation of a result established generically in the Finite Cognition series: a finite observer serving both a committing execution demand and a wide-field vigilance demand is forced to partition the two and re-couple them at the point of finalisation, so that no output is committed that vigilance has not verified. We show that quantum control information forces exactly this construction — telemetry is consumed by every layer of the control stack yet governed by none of them; observation of a quantum plant must be non-perturbative by discipline, not by hope; and an estimator that is fluent but ungoverned reproduces, on the control substrate, the same confident-and-blind failure the series identified generically. We then state the architecture that discharges the constraint, in its public units: a non-perturbative observer (NPO); the QCK detection floor; fail-closed gates that allow, abstain, or refuse; a state-coherence and equilibrium discipline over commits; provenance-checked memory that refuses known-failure patterns; a lifecycle and loop supervisor; a measurement plane of stability, coupling, margin, and cost features; and an integrity plane that audits the architecture’s own calibration model and gates its portability to new hardware on provably leak-free relocation. We are explicit about maturity throughout: the kernel is demonstrated at Technology Readiness Level 4 under published bounds; the architecture beyond it is compile-ready geometry — derived, specified, and internally consistent, not validated as live middleware on partner hardware. The architecture is advisory by construction: the operator owns the plant at every depth.
Cryogenic control electronics for quantum hardware accumulate systematic, non-zero-mean bias that integrates in a feedback loop until the actuator saturates; a threshold controller detects this only after saturation. We present a precursor estimator that detects the onset of systematic drift from the dynamics of the control signal, built as a finite observer (declared error budget, explicit competence boundary, fail-closed abstention) in the sense of a companion paper on the physical limits of finite observation. It uses path-functional invariants (a Fisher–Rao metric stability bound, a maximum-likelihood bias decoder, a cumulative-damage functional) rather than eigenvalue analysis, which we show is neither necessary nor sufficient for finite-time survival. In simulation, across 30 seeds × 7 sensor-environment conditions (including a 1/f dephasing spectrum), it detects 96.7% of drift-collapse scenarios before saturation at a 12 s median lead with 0% false positives over 210 healthy runs. On real data, the same governed outlier-and-drift detector, applied to live publicly accessible IBM quantum-hardware calibration time-series (a 156-qubit IBM Heron device), flags genuinely degraded qubits and catches a real relaxation-time decline (one qubit's T1 falling 88.0→19.1 µs, −78%, over 43 days) while staying silent on a qubit that is poor but stable and on the other 155 — detection of change, not of mere badness. The work is TRL 4: an advisory detection layer, not a deployed controller, and it does not emulate entanglement, non-local correlation, or contextuality. The contribution is the integrated, calibrated estimator and its operating discipline, demonstrated in simulation and against real hardware-calibration data.
Cryogenic control electronics accumulate systematic, non-zero-mean bias — from thermal cycling of mounts, flux leakage, and dielectric memory — that a feedback loop integrates until its actuator authority is exhausted and the integrator saturates. A controller that alarms on amplitude thresholds sees this failure only after correction is no longer available. This paper reports a precursor estimator that reads the dynamics of the control signal for the onset of systematic drift, built deliberately as a finite observer in the sense of the first Finite Cognition paper: a declared error budget, an explicit competence boundary, and fail-closed abstention. Its evidence is presented in two declared strata. First, a fresh, fully archived Monte-Carlo run of record on a declared control-loop model: across 30 seeds × 7 sensor-environment conditions × two drift polarities, with every threshold frozen before the batch, the estimator detected drift before saturation in 246/354 eligible collapse runs (69.5%, 95% interval 64.5–74.1%), with per-condition detection ranging from 25.5% (all disturbances combined) to 100% (dropout; 92.4–100), median leads of 7–17 s, and zero false interdicts across 210 healthy runs within the declared calibration window (0.0–1.8%) — a bound the long-horizon batch shows is conditional on the mandated recalibration schedule. Second, an archived read of live IBM quantum-hardware calibration telemetry (a 156-qubit Heron device, June 2026): the same governed detector family flagged the two genuinely degraded qubits and the sole sustained relaxation-time decline within that window (T_1 falling 88.0 → 19.1 µs across 43 returned calibration snapshots spanning 42 calendar days) — an event a longer archived record later resolves into the first, longest and deepest of four recurring excursions on the same qubit, at a cost to this detector family the paper states while staying silent on a bad-but-stable qubit and the 154 others. The estimator holds advisory-only authority under the programme's interface contract: it emits verdicts and writes nothing to the plant. This record supersedes an earlier version whose simulation table could not be traced to a quantum-specific run; the run of record reported here, code and data archived, is the evidence this paper stands on.
Scalable quantum processors require control, readout, feedback, calibration, and error correction to coexist under bounded latency and shared-resource constraints, whereas existing platforms typically optimize only a subset of these capabilities. This article presents QCORE (Quantum-Control-Oriented Real-Time Execution), a QPU-side digital control reference architecture positioned between the Host and a platform-specific analog/mixed-signal front end. QCORE separates task management, shared resources, hard-real-time execution, and long-timescale services into four hardware partitions. A fast-result sideband closes same-round feedback, a Measurement Packet provides a traceable measurement and service interface, and a common service-control skeleton, Tile-local QEC, and versioned safe-point commit organize calibration, error correction, and long-term state updates. Transaction-level, event-driven, and quantum-behavioral models are used for evaluation. At a background load of 0.8, the P99 latency of the shared Measurement Packet/Event feedback path is (1.984±0.004)Lmax. Closed-loop operation reduces the mean frequency error by 83.2%±0.8% and lowers the state-assignment error at maximum readout drift from 10.39%±0.54% to 5.37%±0.29%. No unsafe acceptance or mixed-version observation is observed in 100,000 configuration transactions, and Tile-local QEC reduces modeled global-boundary demand and yields a 2.08× capacity-normalized scaling estimate.
Cryogenic control electronics for quantum hardware accumulate systematic, non-zero-mean bias that integrates in feedback loops until actuator saturation. We present a precursor estimator that detects the onset of systematic drift from control-signal dynamics before saturation. Designed as a finite observer, it operates to a declared error budget, carries an explicit boundary of competence, and abstains—fails closed—outside it. The estimator uses path-functional invariants rather than eigenvalue or linearisation analysis. In simulation across 30 seeds and seven sensor-environment conditions, it detects 96.7% of drift-collapse scenarios before saturation, with a 12-second median lead and 0% false positives across 210 healthy runs. Applied to live, publicly accessible IBM quantum-hardware calibration time-series from a 156-qubit IBM Heron device, it flags degraded qubits and detects a real relaxation-time decline while raising no alarm on a poor-but-stable qubit or the remaining 155 qubits. This is a TRL-4 detection layer: advisory, validated in simulation and on hardware calibration data, and not a deployed controller.
Abstract Long-run quantum execution remains fundamentally constrained, not primarily by gate infidelity, but by cumulative instability of the rotating phase reference during runtime. While contemporary quantum control stacks rely on calibration, dynamical decoupling, and quantum error correction, these mechanisms operate reactively and assume that the underlying phase frame remains valid between interventions. This assumption breaks down as execution depth, runtime, and system size increase. This note reframes long-run execution failure as a phase-frame stability problem rather than a post-fault correction problem. Using empirical hardware-adjacent observations, it shows that longitudinal drift is structured, temporally correlated, and often collective across qubits, placing it outside the effective bandwidth of fast-noise suppression techniques. As a result, computation is frequently admitted under metastable conditions in which logical error amplification occurs despite unchanged physical gate metrics. Based on this empirical and structural analysis, the note identifies a missing architectural element: a preventive drift-bounding layer that constrains phase-frame deviation before execution proceeds. The argument is intentionally architectural rather than implementational. No hardware-specific parameters, algorithms, or corrective primitives are disclosed. The purpose of this document is to establish why scalable quantum execution requires preventive phase stabilization at the execution boundary, and why reactive correction alone cannot remove this limitation. Detailed theoretical foundations, validation pathways, and hardware-compatible realizations exist but are intentionally excluded from this public note.