QF Solver 0.2.5a0 Owner review: 025-G04¶
Decision identity¶
| Field | Value |
|---|---|
| Gate | 025-G04 |
| Owner decision | REQUIRED |
| Qualified source SHA | recorded in results/vnv_0_2_5/g04_latest/evidence_manifest.json |
| Qualified source worktree | CLEAN at evidence start |
| Evidence pack | results/vnv_0_2_5/g04_latest/ |
| Evidence manifest | results/vnv_0_2_5/g04_latest/evidence_manifest.json |
| Contract lowered | NO |
This review records the available evidence and the reasons the gate cannot be closed. It is not a release decision and does not authorize a tag, push or package publication.
Contract audit¶
The G04 contract requires all of the following in the same bounded scope:
- a true FEM branch crossing a limit point and continuing post-limit;
- complete load-factor/displacement and reaction histories;
- a coarse/medium/fine/refined branch study, or an explicit Owner-approved bounded refinement decision;
- restart before or near the turn, plus controlled rollback and retry;
- analytical or published branch reference;
- the mandatory Code_Aster external correlation of the complete branch;
- clean-source provenance and digest-controlled evidence.
The contract does not accept a reduced shallow-arch model as a FEM proof, does not accept Newton convergence alone, and does not allow a monotone external path to stand in for a missing post-limit correlation.
Evidence assessment¶
QF Solver common-driver FEM¶
The common-driver run is a genuine sparse two-element TET4 path:
| Quantity | Observed value |
|---|---|
| Nodes / global DOF | 5 / 15 |
| Continuation steps | 80 |
| Arc-length radius | 0.02 |
| Control DOF | 14 |
| Load-factor range | [-0.0373265418, -0.0007272447] |
| Control-displacement range | [-0.9419440185, -0.0115649488] |
| Turning points | 1, around step 75 |
| Maximum relative residual | 2.8114e-11 |
Minimum det(F) |
0.4414340033 |
| Evidence status | PASS_INTERNAL_RESEARCH |
The signed load factor reverses between steps 76 and 77 while the control
displacement continues. The targeted tangent diagnostic finds the smallest
reduced-tangent eigenvalue crossing from positive to negative at the turn,
with a reassembled free residual below 5e-13 and positive det(F). This
demonstrates the intended internal branch diagnostic, but it is still a
minimal research path and not a qualified FEM release scope.
Restart and rollback¶
The controlled internal helpers pass restart checks before and after the
observed turn. They reproduce the continuation suffix, displacement endpoint
and material state. The adversarial run injects a failure after two Newton
corrections at step 76 and records a radius reduction from 0.02 to 0.01
with a clean retry.
These results are PASS_INTERNAL_RESEARCH. They do not provide the missing
external correlation or mesh study.
Reduced analytical reference¶
The reduced shallow-arch equation remains useful for algorithmic verification and crosses its analytical limit point. It is not a finite-element reference for closing G04.
Code_Aster external branch diagnostic¶
The historical Code_Aster result was an executed configuration mismatch, not a
solver disagreement. QF applies a positive reference force with a negative
load factor, hence the physical loading is downward; the old Code_Aster deck
applied FZ=+1/3 and followed the upward branch. It also measured the mean
CROWN/DZ, while QF controls apex node N5 UZ (global DOF 14), and used an
unmatched continuation window.
The corrected pinned Docker replay uses the same unperturbed two-element TET4
geometry, FZ=-1/3, APEX/DZ, and a 0..0.96 window sampled at 160 intervals.
It produces a complete branch and one turning point. QF-versus-Code_Aster is
compared by apex displacement, because the solvers do not use the same
arc-length parameterization:
| Quantity | Observed value |
|---|---|
| Image | simvia/code_aster@sha256:4629a21a109309bb97fbdc27d750445cc869e151e2e2ed6290f69539614e4435 |
| External path | complete |
| External turning points | 1 |
| Maximum branch load-factor difference | 4.8719e-07 |
| Peak-normalized maximum difference | 1.3052e-05 |
| Turning-load difference | 6.3485e-08 |
| External diagnostic status | RESOLVED_CONFIGURATION_MATCH |
This is bounded code-to-code diagnostic evidence. It removes the historical
external-deviation blocker but is neither physical validation nor sufficient to
close G04 on its own. The detailed parameter audit is recorded in
0_2_5_g04_external_branch_diagnostic.md.
Gate decision¶
025-G04 = OPEN
OWNER DECISION = REQUIRED
MESH DECISION = OPEN_MISSING_REQUIRED_LEVELS
CODE_ASTER = RESOLVED_CONFIGURATION_MATCH
CONTRACT LOWERED = NO
Exact remaining blockers¶
- Link and reproduce a published FEM snap-through branch reference. The current two-element configuration is custom and no exact public reference has been identified.
- Execute and archive the required coarse/medium/fine/refined arc-length branch study, or obtain an explicit bounded-refinement Owner decision.
- Regenerate a final controlled G04 pack only after the preceding evidence is available.
Until these blockers are addressed, no qualified arc-length production claim is made. G03, G05 and G06 remain unchanged.