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P103 — AIEP — Quantum-Assisted Branch Plausibility Pre-Evaluation

Publication Date: 2026-03-01 Status: Open Source Prior Art Disclosure Licence: Apache License 2.0 Author/Organisation: Phatfella Ltd Schema: AIEP_OS_SPEC_TEMPLATE v1.0.1 — https://aiep.dev/schemas/aiep-os-spec-template/v1.0.1

Framework Context

[0001] This disclosure operates within an Architected Instruction and Evidence Protocol (AIEP) environment as defined in United Kingdom patent application number GB2519711.2, filed 20 November 2025, and GB2519798.9, filed 20 November 2025, the entire contents of which are incorporated herein by reference.

[0002] The present disclosure extends the quantum alignment layer defined in GB2519798.9 to the specific application of quantum-assisted branch plausibility pre-evaluation as a classical resource allocation gate, while remaining independently implementable as described herein.

Field of the Disclosure

[0003] This disclosure relates to quantum-classical hybrid computing architectures for governed artificial intelligence reasoning substrates.

[0004] More particularly, the disclosure concerns a mechanism within an AIEP substrate for using quantum superposition to simultaneously evaluate the plausibility conditions of multiple archived reasoning branches before committing classical computing resources to full branch reactivation evaluation, such that the quantum pre-evaluation functions as a classical resource allocation gate with deterministic fallback to classical pre-evaluation when quantum hardware is unavailable.

Background

[0005] Governed reasoning substrates operating at scale maintain large numbers of archived reasoning branches. At each evidence admission event, the anticipatory branch surfacing mechanism must evaluate whether newly admitted evidence satisfies the reactivation conditions of any archived branch. As archived branch count grows, this evaluation scales linearly with branch count — a significant computational constraint.

[0006] Classical approaches to reducing evaluation cost include: selective evaluation using heuristic pre-filters; probabilistic sampling of archived branches; and batched evaluation on reduced evidence representations. These approaches trade evaluation completeness for computational efficiency — some reactivation events may be missed.

[0007] A quantum computing approach offers a different reduction: quantum superposition represents multiple branch plausibility states simultaneously, evaluating a plausibility-relevant property across all branches in a single quantum operation, and collapsing to a classical result identifying which branches meet the threshold for full classical evaluation. No branches are excluded from consideration before the quantum operation; all are evaluated simultaneously.

[0008] Existing systems do not provide: quantum superposition encoding of archived branch plausibility states for simultaneous evaluation against incoming evidence; a quantum-classical interface producing a PlausibilityPreEvaluationResult; deterministic classical fallback when quantum hardware is unavailable producing an equivalent result without altering downstream evaluation; cryptographic binding of each PlausibilityPreEvaluationResult to the evaluation path that produced it; or governance chip attestation of quantum evaluation path results before admission to the classical evaluation gate.

Summary of the Disclosure

[0009] A PlausibilityStateEncoder encodes the ReactivationConditionProfile of each archived branch as a quantum state register. Encoding is deterministic: identical ReactivationConditionProfiles under the same encoding schema version produce identical quantum state registers. Encodings are pre-computed and cached when branches are archived.

[0010] Upon admission of new evidence, the incoming evidence is encoded as a Quantum Query Register. A Quantum Evaluation Operation — a parameterised quantum circuit — is applied to the combined state of all encoded branch registers and the query register, implementing the plausibility matching function across all branches simultaneously through superposition. Quantum measurement produces a PlausibilityPreEvaluationResult: the set of branch identifiers whose plausibility states collapsed to the compatibility indicator.

[0011] Full classical reactivation evaluation is applied only to branches appearing in the PlausibilityPreEvaluationResult. Branches not in the result are not subjected to full classical evaluation for that evidence admission event.

[0012] In hardware-enabled deployments, the PlausibilityPreEvaluationResult is attested by the governance chip before use as a classical evaluation gate. The governance chip computes a PreEvaluationHash = H(CanonicalSerialise(PlausibilityPreEvaluationResult) ‖ EvaluationPath ‖ IncomingEvidenceHash ‖ Timestamp) and attests it via the standard attestation mechanism. An unattested result causes fallback to classical simulation.

[0013] Classical Fallback: When quantum hardware is unavailable or the quantum evaluation operation fails, a PlausibilityPreEvaluationSimulation applies the same plausibility matching function in classical sequential computation. The PlausibilityPreEvaluationResult produced is identical in structure and interpretation. The downstream classical reactivation evaluation mechanism is identical regardless of which path produced the result.

[0014] A PreEvaluationPathRecord is appended to the Reasoning Ledger at each evidence admission event comprising: evaluation_path (“QUANTUM” or “CLASSICAL_SIMULATION”); PlausibilityPreEvaluationResult; incoming_evidence_hash; PreEvaluationHash; and timestamp.

[0015] The completeness guarantee: the probability that a branch warranting full classical evaluation is absent from the PlausibilityPreEvaluationResult is bounded by the schema-defined quantum circuit fidelity parameter. When fidelity falls below the schema-defined minimum, the substrate automatically falls back to classical PlausibilityPreEvaluationSimulation, which provides exact completeness.

Brief Description of the Drawing

FIG. 1 — Quantum Alignment Layer

   ┌──────────────────────────────────────────┐
   │          Quantum Alignment Layer         │
   │                                          │
   │  |ψ⟩ = α|canonical⟩ + β|divergent⟩      │
   │                                          │
   │   State v1 ◀──── phase coherence ─────▶ State v2
   │      │                                    │
   │      └──────────── Δφ (alignment) ────────┘
   │                         │                │
   │              ┌──────────▼──────────┐     │
   │              │  Alignment Score    │     │
   │              │  S = 1 − |Δφ| / π  │     │
   │              │  threshold: θ_min   │     │
   │              └─────────────────────┘     │
   └──────────────────────────────────────────┘

Licence

Licensed under the Apache License, Version 2.0 (the “License”); you may not use this file except in compliance with the License. You may obtain a copy of the License at https://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an “AS IS” BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.