QC-020 Dual-Path Qualification (OQ/PQ vs Live Miner)

Document ID: gaiaftcl.qc020.dual_path.v1

Companion: QC21_QUANTUM_VM_VALIDATION_REVIEW.md, PEER_REVIEW_QC020_QC021_CIRCUIT_REWRITE.md, GAMP5_QUALIFICATION.md

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1. Why two parallel paths

Bitcoin PoW qualification must not conflate:

Path	Clock	Claim	Purpose
QC-020-HIST	Decoupled (no mempool race)	`pow_ledger_oq_pq`	OQ/PQ: sealed headers, ExtraNonce, Merkle root as static entropy
QC-020-LIVE	Template window (~30s) inside network thermodynamic window (~10min)	`pow_live_miner_l7_l8`	Close the window, learn, adjust live miner

Algorithmic qualification is independent of the live network clock. Any historical block is a globally verifiable test vector for the QA primitives.

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2. Historical deterministic path (OQ/PQ)

Inputs: qc020_difficulty_ledger rungs + frozen block 100000 vector (V152 seed).

Checks:

1. Swift verify_qc020_rungs — CryptoKit digest ↔ ledger literals ↔ target

2. Block 100000 — nBits=0x1b04864c, nonce=274148111, header hex sealed in chain state

3. Substrate invoke — SubstrateAmplitudeAmplifier.amplifyAgainstSHA256Oracle on historical header shape (easy target for OQ invoke proof; real difficulty verified in step 1–2)

Reproducibility: Lean BTCPreimageLarge.lean codegen from ledger; infinite re-runs return the same algebra.

Export: evidence/research/qc020_dual_path_latest.json → paths[QC-020-HIST]

cells/xcode/scripts/export_qc020_dual_path_research.sh

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3. Live window-limited path (miner)

Inputs: QC020Surface + five-window orchestrator + M8BTCSubstrateMiner.

Constraint	Value
Template TTL	30 seconds (`QC020Surface`)
Parallel windows	5 disjoint S⁴ embeddings per template
Network clock	~600s between blocks (thermodynamic invariant)
L8	`qc020_substrate_research_telemetry` — Grover-bound law
L7	`onChainRewardOK` only when `chain_accepted` (never simulated)

Export: same JSON → paths[QC-020-LIVE] + liveWindowPolicy

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4. Substrate backend honesty

Circuit family	Backend	Notes
QC-001…QC-021 (except PoW)	`vqbit_metal`	Metal-only; no CPU fallback
QC-001-ECDLP	`vqbit_metal`	`QC001_ECDLP.metal`
QC-020 PoW	`vqbit_cpu_projection`	`M8MeasurementComposer` + SHA256 oracle; Metal shader exists but `metalQC020Ready=false`

Research export carries substrateComputeBackendNote so reviewers do not read global vqbit_metal as applying to PoW projection.

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5. Substrate bypass audit

The dual-path export includes substrateBypassAudit — known non-production paths:

Location	Role	Mitigation
`BitcoinPreimageOracle.classicalEvaluate`	Verifier only	Not a search loop
`M8QC020BootstrapRungCapture`	Ledger seed	Classical bootstrap; preflight blocks `classical-placeholder` producers
`find_nonce` in `BTCPreimageLargeGate`	Codegen	Offline ledger seed only
`QC020_BTCPreimage.metal`	Orphaned shader	Not wired to production path
`BTCPreimageLarge.lean`	Codegen Lean	Deferred from strict export until ledger sync

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6. Publication checklist

# Dual-path row
cells/xcode/scripts/export_qc020_dual_path_research.sh

# Full VM matrix (includes qc020DualPath in validation block)
cells/xcode/scripts/peer_review_research_dataset.sh

# Unit/integration
cd cells/xcode && swift run VQbitMathTestRunner
cd cells/xcode && swift run M8QC020DualPathQualificationEval

Frozen artifacts:

File	Schema
`evidence/research/qc020_dual_path_latest.json`	`gaiaftcl.qc020.dual_path.v1`
`evidence/research/qc_vm_validation_latest.json`	`gaiaftcl.qc_vm.research.v4` with `validation.qc020DualPath`

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7. Franklin / Python (GAMP 5)

Historical block ingestion for Sprout OQ/PQ:

1. Pull getblockheader(height) (or use frozen block 100000 from ledger)

2. Feed header prefix + nBits target into vQbit VM QC-020 invoke

3. Compare substrate LVC + ledger literals → audit artifact

Franklin Python socket (local operator host):

{"method": "historical_block_header", "args": {"height": 100000}}

Returns frozen corpus fields (header_hex, header_prefix_hex, nonce, nbits_hex, target_decimal, clock_decoupled: true). Live getblockheader for other heights: QC020HistoricalBlockReplay.resolve(height:client:).

FranklinClient.research_telemetry and evaluate_algorithm document the live path.

Federation cosignature: pending operator signing host (v26). Witness (sha256 of rendered body): 7534845c2008596ec9dbe3f78f8f97481e16e8019a59bc54b1caf3d647ee9578. This page serves with a substrate-honest pending-signature notice until the operator's Franklin signer cosigns it.