Sustained Attractor Diversity in Doubt-Modulated FitzHugh--Nagumo Networks: Spectral Dead Zone and Chimera States on Scale-Free Topologies

V4.0.0 — Audited Stable (2 May 2026) This release formalizes the V4 scientific results following systematic adversarial review. Key findings: Spectral dead zone: λ₂_crit = 2.31 separates functional and collapsed regimes (logistic regression, 100% accuracy, n=36) u = anti-synchronization filter: FROZEN_U ablation produces +985% synchrony surge (factor ×10.9) Topological intelligence: hub trajectory complexity correlates with degree (r=−0.716, p=1.29e−79) Event-driven phase transition: peripheral forcing outperforms hub forcing (+1.20 vs +0.21 bits) Chimera states mechanistically distinct from Abrams-Strogatz 2004 (R=0.141 vs R=0.766) Hardware validation: Dead zone confirmed in SPICE (ngspice 46), BA m=5, N=64, 50 seeds — 3.1× ratio. Test suite: 84 automated tests — 0 failures. Companion document: Results Compendium (COMPENDIUM.pdf) — 4-page typeset brief covering all findings, robustness experiments, and reproduction instructions. GitHub: https://github.com/cafe-virtuel/Mem4ristor