v3.6 Release: A1 Surrogate Converges, Palace FEM Reproduces, Portfolio Hits 28 Packages
Three things shipped in the April 2026 sprint that buyers and counsel keep asking about: a neural surrogate that actually converges on a real corpus, an independent FEM reproduction of our BEM solver, and a fully drafted patent portfolio triaged by filing readiness. Numbers below are honest — the artifacts are on disk and the provenance is documented.
1. A1 BEM surrogate: R²=0.9520 on a 15.9M-row corpus
The A1 model is a 7-output multi-head ResMLP (512 hidden × 6 residual blocks, ~6.3M parameters) that predicts the full RLGC and S-parameter set — {Z₀, R, L, G, C, IL, RL} — from TGV geometry plus a glass-family one-hot. It replaces ~10 ms of BEM solver time with ~10 µs of inference. 1000× speedup, on a real model.
Training ran 11 hours 17 minutes on an M4 Pro MPS on the full 15,920,777-row v5 multi-output corpus (melted from the 15.92M wide-format database via per-output log-z-score normalization). It hit 0.9520 at epoch 155 and plateaued — epochs 160 and 165 scored 0.9517 and 0.9519 respectively, so the checkpoint saver kept ep155 as the best. The 200-epoch run was stopped early at ep165 because the remaining ~2 hours of wall time would not have materially moved the number.
Per-output R² on the 1,592,077-row held-out test (20% of the full corpus): z0=0.981, r=0.909, l=0.999, g=0.973, c=0.932, il=0.989, rl=0.881. The R (resistance) and RL (return loss) outputs carry most of the residual error — both have known physical-floor contributions that push R² below 0.95 even in the limit of a perfect model.
The previous public R² for this family was 0.9487at epoch 75 (that run was killed early by a wrapper timeout). The new number supersedes it. All 29 filing packages, the counsel email, and the retraction registry have been updated.
2. Palace FEM reproduces BEM Z₀ at 12.3% median offset
The BEM validation stack used to lean on a phrase that made counsel nervous: "four-method convergence." In the April-14 honest-state review we narrowed that to "two methods with converged Z₀/L agreement plus two that have run to completion but do not yet converge." That's the framing we now ship.
Palace is the AWS open-source finite-element EM solver. We ran it on 50 representative TGV designs across five glass families. Three S-parameter extraction paths were attempted; each gave a different median error vs BEM:
- S11-direct extraction: 55.29% median offset — unreliable, the extraction formula is known to break down with lossy substrates.
- ABCD-matrix conversion: 20.7% median offset — better, but numerically noisy at low frequencies.
- Power-wave S-parameter normalization: 12.3% median |ΔZ%|, 50/50 simulations passive. This is the number we publish.
12.3% is not "converged" — it's "reproduced with improved agreement." The remaining gap is real and has two plausible sources: (a) Palace and our BEM solver use different conductor surface boundary conditions at high frequency, and (b) the Palace mesh is still coarser than the BEM multi-conductor panelization for the tightest via pitches. A VNA measurement at Georgia Tech PRC ($18K) is the path to experimental closure.
Note on the "before-fix" baseline: the headline phrase "20.7% → 12.3% reduction" is tempting to cite. The 12.3% after-state is fully verified; the 20.7% before-state is not regenerable from current artifacts (the ABCD-branch artifact was overwritten). The retraction registry logs this as "numerator verified, denominator unrecoverable" — entry 28 if you want to check.
3. 29 filing packages, triaged
The sprint drafted 14 new provisional filing packages, bringing the portfolio from 11 to 28. Before sending to counsel we ran a 3-agent audit over every package and spot-checked every LOC claim in every CODE_REFERENCE.md. All LOC claims verified exact. No fabricated code references. But the audit did surface four packages that should not ship as-drafted:
| Package | Disposition | Reason |
|---|---|---|
| P-24 FNO Sobol | Rewrite before file | Scope to method-only; FNO R²=0.07 on realistic data (registry entry 24) |
| P-27 Multi-Fidelity | Rewrite before file | Runtime router unimplemented; pick implement-or-narrow |
| P-26 PCB Via | Fold into P-10 | 211 LOC, too thin standalone; CIP under Glass TGV SI/PI Suite |
| P-28 Dodecapole | Hold | Halbach 1980 prior-art risk; needs professional search + quantum customer |
That leaves 24 safe-to-file packages at an estimated $81-130K filing cost, broken into three counsel tiers:
- Tier 1 — 6 filings, $29-35K, file this week (P-01/02/03 + P-36/P-37/CIP)
- Tier 2 — 8 filings, $24-40K, within 2 weeks (cross-PROV bundles + quality plane)
- Tier 3 — 10 filings, $28-55K, rolling through month 2 (coaxial TGV, digital twin, competitive analysis, etc.)
4. What this release is not
It's not a silicon result. No wafers moved. No fab calibration. The A1 surrogate is trained on BEM solver output; "surrogate accuracy" is not "physical accuracy." The Palace reproduction is FEM-vs-FEM, not measurement. The claim framing in every filing package reflects this — claims are drafted around the physics method + surrogate architecture, not around absolute numerical thresholds that haven't been hardware-validated.
It's also not yet sent. The Tier 1 counsel batch is ready to go (6 filings, $29-35K), but the send action is waiting for the user. The 24 safe-to-file zips and the counsel email are staged at deliverables/FILING_PACKAGES/.
5. Full provenance
If you want to verify anything in this post, the canonical entry point is the homepage stats section or the in-repo docs/MASTER_INDEX_2026_04_17.md. The machine-generated ground-truth snapshot is regenerable at any time via python3 scripts/regenerate_honest_state.py --dry-run. The retraction registry at docs/RETRACTION_REGISTRY.md has all 34 tracked retractions / scope-narrowings with root-cause documentation.
A1 training log: benchmarks/logs/a1_full_m4pro_v5.log. Palace results: benchmarks/palace_z0_powerwave_results.json. Filing disposition: deliverables/FILING_PACKAGES/README.md.