Commit graph

2 commits

Author SHA1 Message Date
Brandon Schneider
4965029758 feat: integrate May 2026 math papers into Research Stack
1. Singer Sidon Sets (2605.03274):
   - New SidonSets.lean: IsSidon, IsSidonMod, IsIntervalSidon, h(N)
   - 5 fully proved lemmas, 13 sorry with TODO(lean-port)
   - GoldenRatioSeparation.lean: singer_density_lt_golden (proved)
   - lake build: 3303 jobs, 0 errors

2. Hexagonal lattice + RG (2605.09974):
   - New test_hexagonal_lattice_rg() in unified_rg_tests.py
   - Avila's global theory exact phase diagram
   - RG confirms localized/extended regimes
   - Fractal dimension: extended→1, critical→0.5, localized→0
   - 7 tests, all pass

3. Burgers + Hopf-Cole + Fokas (2605.11788):
   - Added solve_heat_fokas() — unified transform method
   - Added solve_burgers_fokas() — full Burgers via Hopf-Cole + Fokas
   - Added solve_heat_fourier_series() — comparison solver
   - Fokas converges in ~64 quadrature points vs Fourier 2000 terms
   - Hopf-Cole FFT: 8-208x faster than finite differences
2026-05-30 18:16:57 -05:00
Brandon Schneider
a53e023cbe feat: Hopf-Cole exact solver for 1D Burgers — 151x speedup
Hopf-Cole transformation maps Burgers to heat equation:
  u = -2v * d(ln ψ)/dx
  dψ/dt = v * d²ψ/dx² (exact via FFT)

Benchmark results:
  N=512,  v=0.01: 1.45x speedup
  N=1024, v=0.01: 83.4x speedup
  N=2048, v=0.01: 151.3x speedup

Key insight from adversarial review:
  - RG assumption (nonlinear term vanishes) is FALSE
  - But 1D Burgers IS integrable via Hopf-Cole
  - Exact solution in O(N log N), no time stepping
  - The 'insultingly easy' regime exists — just not via RG

This is the exact solution the agents found when they
broke the RG fixed point assumption.
2026-05-30 17:36:12 -05:00