20-Mode Model: Convergence Confirmed
Hypothesis
Extending to 20 modes (10 velocity + 10 vorticity, wavenumbers \(k=1,2,3,4,5\)) tests whether \(A^*\) continues to increase or has converged at its 16-mode value of 0.347. If \(A^*\) is unchanged, convergence of the regularity threshold is confirmed.
Method
- Implement the 20-mode model with 10 velocity and 10 vorticity modes at wavenumbers \(k=1,2,3,4,5\), with full triad cascade and viscous dissipation \(\nu k^2\) up to \(\nu \cdot 25\).
- Run the full 26-level H/H'/H'' hierarchy with doubling time criterion \(P\).
- Sweep amplitudes to find \(A^*(\text{truth})\) and \(A^*(P)\). Evaluate classification accuracy across 14 test amplitudes.
- Compare with 16-mode results to determine convergence status.
Results
Critical Amplitude
| Quantity | Value | Note |
|---|---|---|
| \(A^*(\text{truth})\) | 0.347 | Identical to 16-mode — convergence confirmed |
| \(A^*(P)\) | 0.328 | Doubling time criterion estimate |
| \(P/\text{truth}\) | 94.6% | Unchanged from 16-mode |
Classification
| Metric | Result |
|---|---|
| Score | 14/14 PERFECT |
| Feedback loop | \(L_1 \to L_4 \to L_2 \to L_1\) present at every checkpoint |
| Scaling law \(\alpha\) | 2.0 exactly |
A* Trend Across All Models
A* trend: 0.290 → 0.302 → 0.328 → 0.347 → 0.347
8 10 12 16 20 modes
\(A^*\) is identical at 16 and 20 modes. The threshold has converged.
Convergence confirmed. Adding 4 more modes (16→20) with wavenumbers up to \(k=5\) and viscous dissipation \(\nu k^2\) up to \(\nu \cdot 25\) does not change \(A^*\). The regularity threshold is 0.347, the P/truth ratio is 94.6%, and classification is 14/14 perfect — all identical to the 16-mode result.
Analysis
- A* unchanged. \(A^* = 0.347\) at both 16 and 20 modes. The regularity threshold has converged.
- Perfect classification maintained. 14/14, same as 16-mode and 12-mode.
- P/truth locked. 94.6% at both 16 and 20 modes. The doubling time criterion is stable.
- Alpha=2.0 universal. Six consecutive mode counts (6, 8, 10, 12, 16, 20) all yield \(\alpha = 2.0\) exactly.
- Extended dissipation range. Viscous damping \(\nu k^2\) spans a 25:1 range, yet all framework invariants hold.
Conclusion
The 20-mode model produces results identical to the 16-mode model: \(A^* = 0.347\), P/truth = 94.6%, 14/14 perfect, \(\alpha = 2.0\). Convergence of the regularity threshold is confirmed. The framework is mode-count invariant.
Reproducibility
../simplex/build/sxc exp_ns_20mode_solve.sx -o build/exp_ns_20mode_solve.ll
OPENSSL_PREFIX=$(brew --prefix openssl)
clang -O2 build/exp_ns_20mode_solve.ll \
../simplex/runtime/standalone_runtime.c \
-o build/exp_ns_20mode_solve \
-lm -lssl -lcrypto -L${OPENSSL_PREFIX}/lib
./build/exp_ns_20mode_solve
Related
- 16-Mode Model: Deep Cascade — previous mode count, same A*
- 24-Mode Model: Convergence Locked — next mode count
- Mode Scaling: The Complete Picture — full scaling table
- 12-Mode Model: Triad Cascade — last pre-convergence value