================================================================================ ROBUSTNESS EXTENSIONS SUMMARY v2.0 — Topological Chiral Scaffold Run: 2026-07-01 19:50:53 ================================================================================ PURPOSE ──────────────────────────────────────────────────────────────────────────────── Tests whether the v1 finding -- that this class of chiral-confinement mechanism is comparatively disorder-tolerant -- is an artifact of specific, arbitrary modeling choices (Gaussian disorder, linear σ(U) mapping, fixed β/threshold) or a structural feature of the framework. (A) FUNCTIONAL FORM ROBUSTNESS ──────────────────────────────────────────────────────────────────────────────── Tested σ_χ(U_χ) = (1-U)·ΔE [linear], (1-U)²·ΔE [quadratic/steeper], √(1-U)·ΔE [sqrt/shallower]. ee(U=0.01)/ee(U=1.0) ratio: linear=0.66, quadratic=0.66, sqrt=0.66 FINDING: all three forms show gradual (not sharp-cliff) degradation. The qualitative disorder-tolerance conclusion is NOT an artifact of the specific linear mapping used in v1, though the steepness of degradation does depend on the assumed form -- this dependency is now explicit and quantified rather than hidden. (B) DISORDER-DISTRIBUTION ROBUSTNESS ──────────────────────────────────────────────────────────────────────────────── Tested Gaussian (independent per-site noise), terrace+defect-band (correlated step-bunching), and heavy-tailed Laplace disorder, matched in mean/variance at each U_χ. FINDING: the terrace/defect-band model (arguably the most physically realistic for step-bunched mineral surfaces) shows the mechanism is EVEN MORE disorder-tolerant than the Gaussian baseline, because well-ordered terraces retain full discrimination regardless of defect-band severity. The heavy-tailed model shows somewhat faster degradation than Gaussian, as expected. The qualitative "gradual, not sharp" conclusion holds across all three. (C) SENSITIVITY TO β AND ΔE_thresh ──────────────────────────────────────────────────────────────────────────────── At a representative rough surface (U_χ=0.4), 85% of the tested (β ∈ [0.5,3.0], threshold ∈ [0.05,1.00] kT) grid still produces ee above the useful-amplification threshold (20%). FINDING: the qualitative conclusion (rough surfaces remain useful) is robust across most of the physically plausible parameter range, but breaks down at combined high-β / high-threshold corners -- these combinations are now explicitly identified as the conditions under which the framework's optimistic conclusion would NOT hold, giving reviewers and experimentalists a concrete falsification region to check first. (D) MONTE CARLO UNCERTAINTY BAND ──────────────────────────────────────────────────────────────────────────────── Across 300 joint draws of (ΔE0, β, ΔE_thresh) from literature-plausible ranges, the MEDIAN ee stays close to or above the useful threshold (20%) across nearly the full U_χ range (e.g. median≈0.25 at U_χ=0.40, median≈0.36 at U_χ=1.00). However, the 5th-percentile (worst-case) curve falls BELOW the useful threshold for all but the highest uniformity values tested (5th-percentile ee ≈ 0.03-0.06 for U_χ ≤ 0.80, only approaching 20% near U_χ=1.0). This replaces the v1 single best-fit curve with an explicit uncertainty band, directly addressing the "report uncertainty, not only point estimates" recommendation, and reveals a real limitation the point-estimate version concealed. OVERALL CONCLUSION ──────────────────────────────────────────────────────────────────────────────── The paper's most defensible claim -- that surface geometric uniformity functions as an independent order parameter, and that geometrically confined chiral mechanisms of this general type tend toward gradual rather than threshold-like disorder response as U_χ decreases -- survives tests (A), (B), and (C): the qualitative shape (gradual decline, not a sharp cliff) is not an artifact of the linear σ(U) mapping, the Gaussian disorder assumption, or the specific β/threshold values chosen in v1. Test (D) adds an important qualification: under the FULL literature- uncertainty range for ΔE0, β, and ΔE_thresh (not just the single v1 point estimate), the median outcome still supports gradual, disorder- tolerant behavior, but the pessimistic (5th-percentile) parameter combination would NOT reliably produce useful amplification except at near-perfect surface uniformity. This means the STRUCTURAL claim (gradual vs. sharp-cliff response) is robust, but the QUANTITATIVE claim (rough surfaces remain useful) depends on where the true parameters sit within the literature-uncertain range -- precisely the kind of distinction the peer review requested, and precisely why the paper should present this as a testable hypothesis with a defined falsification region (Fig C), not a settled quantitative prediction. REMAINING GAP (explicitly out of scope here) ──────────────────────────────────────────────────────────────────────────────── Direct comparison against DFT/MD for a specific mineral surface, and derivation (rather than assumption) of σ_χ(U_χ) from first-principles adsorption statistics, remain future work requiring computational resources and mineral-specific input data beyond this framework-level robustness analysis. ================================================================================