Authentic evidence can cease to authorize¶
GA-SYN-002 · Edition 2026.10.8 · Synthetic technical investigation
Proposition and operational question¶
Every admitted use refers to the current document version in all four-event histories over read, change and use, with versions zero and one.
This matters when a continuing task reuses an earlier decision or representation. A final success label can conceal a different failure earlier in the trace. The proposition therefore identifies the exact observation that would refute it.
Definitions, trust and failure model¶
A read records the current version. A change advances the document to version one; later changes leave it there. A use is admitted only if a read exists and its version equals the current version. The scheduler controls event order. Version observation and use are atomic in this model. We assume the version distinguishes every material change and the consumer sees the current version.
Worked synthetic trace¶
Take read, change, use, read. The first event records zero. Change makes the current version one while the recorded observation remains zero. Use is refused; the historical observation is still a correct record of what was read. The final read records one and can support a later use. All 81 length-four histories are evaluated, including use before any read. Missing coverage is refused independently of freshness.
Negative control¶
Remove only the equality check. Read at zero, change to one and use then admits stale evidence. An authenticity check would still accept the original read because the model has not forged it. The negative result demonstrates why an old valid observation and current eligibility require different predicates.
Three evidence records and separate axes¶
| Record | Method and evidence | Scope and status |
|---|---|---|
| Research | Authored finite argument and explicit counterexample, 12 October 2026 | Analytical; limited to the definitions above |
| Reference | My execution, with AI assistance, of the independently designed public teaching case freshness, 12 October 2026 |
Fault-tested; externally reproducible with the commands below; no independent reproduction claimed |
| Production | None for this proposition | No product conformance inferred |
Engineering maturity: reference_implemented, referring only to the disclosed teaching case. Assurance: analytical, fault_tested, externally_reproducible, each restricted to its evidence record. These labels are independent dimensions, not a score or a global verification flag. The exact machine-readable record is in the public evidence catalog. My own runs do not count as independent review.
Limitations and open obligations¶
No physical clock, lease duration, distributed invalidation delivery, authentication, hidden read or dependency discovery is modeled. A real consumer must establish coverage of all material premises before evaluating freshness. The one-step version space does not establish unbounded revocation convergence. Repeated changes with an unchanged version would violate the assumptions.
Prior art and contribution limit¶
RATS distinguishes evidence, appraisal and relying-party decisions. The novelty claim is deliberately limited: this teaching model illustrates a known distinction. A proposed contribution in the wider corpus is retaining that distinction through continued work; that composition remains to be demonstrated. See the primary reference and the comparison guide. No priority or superiority claim follows from this example.
Reproduction and falsification¶
From the successor public source package, use CPython 3.12.14 and no external packages:
python examples/investigations/check.py --case freshness
python examples/investigations/check.py --case freshness --mutant
The first command must exit zero, with no positive violations and at least one negative violation. The second intentionally exits one and prints an actual violated case. It is a deliberate fault result, not an installation failure. Source and reproduction contract identify the exact population and scope.
Submit a counterexample, a missing assumption or a prior-art correction through the review guide. Include GA-SYN-002, edition 2026.10.8, the command, input and output, and whether the objection concerns the model, implementation or proposed product relationship. Do not send credentials or confidential customer material.
For the wider architecture, see the AD8 paper, architecture synthesis, claim register, and AD8 investigation overview. Native reference results and open constructions have separate scope; these examples do not implement them.