Optional top assurance tier

Hardware-conditioned provenance for long-retention evidence.

This is the deepest tier, and most deployments never need it. It sits above the post-quantum signing and offline verification covered in the assurance brief. Reach for it only when a record must survive decades and a later dispute, and an algorithmic signature alone is not enough: it adds measured hardware behavior as a device-conditioned verification signal.

Advanced Evidence Package

Where quantum actually fits

The base layer is deliberately conventional: NIST-standardized post-quantum signatures (ML-DSA/Dilithium), hash-chained events, keys in Vault, KMS, or HSM custody, and local verification through versioned profiles. That layer carries most workflows on its own and is the subject of the assurance brief. None of it requires quantum hardware.

Hardware-conditioned provenance enters above that layer, as the optional top assurance tier. FieldHash Ledger uses hardware-executed measurement distributions as the verification signal for a Quantum Physical Unclonable Function, or Q-PUF: distributions shaped by backend state, calibration, gate behavior, and noise characteristics, producing device-conditioned fingerprints evaluated under disclosed hardware, parameter, and operating conditions. This is a conditioned evidence signal, not proof of physical unclonability across untested hardware. Where hardware is not used, simulation fallback is supported and labeled as a lower-trust tier, never passed off as the real thing.

Physical anchor

Quantum measurements add a hardware-conditioned signal to otherwise algorithmic provenance workflows.

Composed defense

Production verification combines statistical policy gates with integrity signatures and profile controls.

Backend agnostic

Users do not need their own quantum computer; FieldHash Ledger can call available provider APIs today.

PQC is the signing layer. Hardware-conditioned provenance is an additive evidence layer above it for long-retention or disputed-evidence workflows. It does not replace PQC.

What FieldHash Ledger does

FieldHash Ledger turns important digital artifacts into offline-verifiable evidence packages. Each certificate binds content hashes, quantum measurement statistics, backend metadata, policy profile, and cryptographic signatures into a portable trust object.

1

Hash

Bind the artifact with SHA-256/SHA-512 content digests.

2

Execute

Run a parameterized circuit through simulation or available QPU backends.

3

Fingerprint

Capture measurement distributions, noise statistics, and distribution digests.

4

Sign

Bind the evidence package with modern signatures, including post-quantum options.

5

Verify

Validate the certificate later through versioned standard, hardened, strict, or offline profiles.

Evidence, not assertion

The public evidence package documents real hardware execution, adversarial synthesis benchmarks, adaptive spoofing tests, cost data, and reproducibility materials. The claim boundary is explicit: FieldHash Ledger does not claim asymptotic runtime speedup at current scale. It claims security-oriented quantum utility.

HardwareExecuted on IBM Quantum and Quantum Inspire, with auditable job records and reproducibility artifacts.
Standard profileUniform-blend attack accepted in 15/800 trials, a measured soft spot rather than a hidden failure.
Hardened profileThe same attack family was closed to 0/800 under tightened policy settings.
Production gateAdaptive production-gated tests produced 0/5000 successful forgeries per tested model under the no-signing-key assumption.

Next phase

The hardware-conditioned tier is ready for independent validation and carefully scoped pilots. The next work is not to broaden the claim; it is to harden the proof, expand backend conditions, and quantify impact in real document ecosystems.

Independent third-party red teaming against the Q-PUF verification model.
Larger-shot, multi-backend hardware campaigns to expand the operating envelope.
Domain pilots in long-retention regulated workflows where future disputes are expected.
Economic and policy impact modeling aligned to SDG 9 and SDG 16.

The goal is practical: stronger digital trust now, using quantum hardware as a measured evidence source rather than waiting for a fault-tolerant future.

Read the advanced proof package

For qualified technical review, the evidence package includes the preprint, adversarial results, hardware reports, manifests, and reproducibility materials.

Open Zenodo EvidenceBack to the assurance brief