{"id":"z2-abstention-audit-round4","title":"Z2 Spin-Aware Campaign — Abstention Audit","subtitle":"No spin-capable runner, panel, or contract exists; four hash-chained abstention rows, zero cloud spend. Full scope returns with a spin runner.","category":"validation","tags":["z2","magnetism","abstention","round-4"],"source":"articles/docs/campaigns/z2-abstention-audit.md","lang":"en","words":398,"readMinutes":2,"toc":[{"depth":2,"text":"Question","id":"question"},{"depth":2,"text":"Verdict: the campaign cannot be executed honestly — abstention is the preregistered answer","id":"verdict-the-campaign-cannot-be-executed-honestly-abstention-is-the-preregistered-answer"},{"depth":2,"text":"What was produced instead","id":"what-was-produced-instead"},{"depth":2,"text":"Path back to full scope","id":"path-back-to-full-scope"}],"html":"

Z2 Abstention Audit — Round-4 spin-aware multi-fidelity campaign

Status: content-addressed audit · scope amended to abstention by director/owner decision 2026-07-19\nCampaign: discovery.round-4.z2-magnetic-anisotropy.v1 (campaigns/v1/z2.campaign-manifest.v1.json, content hash sha256: per manifest)\nRows: data/candidates/z2/measurements.jsonl (4 rows, RFC 8785, hash chain tail sha256:05d3b087…), data/candidates/z2/artifact-manifest.json\nReconstruction note: the original t_52df7aae deliverable was lost with its kanban scratch workspace. The findings below are re-derived from repository state and match the original audit's claims; the original blocker document's SHA-256 was c0c0e31773fa06d51d7310ffe19de42a59e1db95870ac32636d31e1d5bb450c3. No original content hashes are claimed here; all artifacts in this package carry their own, new content addresses.

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Question

Can the declared available models reproduce the complete held-out\nmagnetocrystalline-anisotropy ordering, including easy-axis sign, on a\nlocked reference panel (frozen hypothesis h.z2.anisotropy-ranking)?

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Verdict: the campaign cannot be executed honestly — abstention is the preregistered answer

The same preregistration freezes the escape hatch: h.z2.scalar-abstention —\n"scalar-energy rows without spin-orbit-resolved evidence abstain and cannot\ncount as ranking successes." Every precondition for honest execution is absent:

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  1. No spin-capable runner. The MLIP cell runner exposes rows\nadsorption_energy, elastic_constants, energy_volume, forces, stress, relaxation_stability (python/lupine_distill/fixture_contract.py,\nROW_IDS) — all scalar energy/forces/stress-derived. No SOC,\nnon-collinear magnetism, anisotropy, or Tc path exists for any declared\nmodel (chgnet 0.4.2; mace-torch 0.3.16 small / medium / mpa-0-medium).
    2. \n
  2. No reference panel. The frozen manifest requires ≥5 held-out SOC/Tc\nreference materials with uncertainties; no such locked panel exists, and\nnone was fabricated.
    3. \n
  3. No ClaimContract. registry/claims/discovery.z2.magnetic-anisotropy.v1.json\ndoes not exist, so no ingestion target can lawfully receive Z2 rows;\nmaterialization stays fail-closed by design.
    4. \n
  4. Tc outside the frozen scope. The manifest preregisters the anisotropy\nordering only; no Tc metric or premise is frozen, so Tc numbers would be\nunpreregistered claims.
    5. \n
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Executing anyway would require fabricating a panel, a runner capability, or a\nclaim — each independently disqualifying. Cloud compute spend for this audit:\nzero executions.

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What was produced instead

Four content-addressed measurement rows — one per declared available model —\neach recording epistemic_status: unsupported, sample_count: 0, and\nacceptance_test.outcome: abstained with the explicit rationale. The rows are\nRFC 8785 canonicalized and hash-chained to the campaign manifest hash, built\ndeterministically by tools/build_z2_abstention_rows.py.

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Path back to full scope

Kanban t_052adac7 (parked per owner decision 2026-07-19 until Z1/Z3/Round-4\nexecution completes): build a spin-aware runner (SOC / non-collinear MAE\nranking + Tc), source an honest published ≥5-material SOC/Tc reference panel\nwith the Z1/Z3 locking conventions, author the missing Z2 ClaimContract, and\namend the manifest to bring Tc into preregistered scope. Only then does this\naudit get superseded by real measurement rows.

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