🔬Where Feasibility Bends: Stable 2D Interaction and the Absence of 3D Structure

First empirical demonstration that feasibility constraints compose non-additively in pairwise combinations but exhibit a dimensional cutoff at n=2
Research Program: UNNS Laboratory Phase P₀–P₂ • Status: Publication-Ready
Foundation: Axis I–V verification (Phase P₀) → Admissibility geometry (Phase P₁–P₂)
Total Evidence: 384,832 independent recursive executions • Methodology: Preregistered with transparent null results
56% non-additive volume 0.580 max residual n≤2 dimensional bound κ=0.309 boundary curvature

🎯 Key Discovery

Building on Phase P₀ verification of Axis I–V substrate stability, we demonstrate for the first time in a recursive substrate that admissibility constraints do not compose independently. When two feasibility gates interact (topological + spectral, or spectral + logical), they create measurable geometric structure: boundaries curve, interaction volumes span 56% of parameter space, and enhancements reach 138% beyond independence predictions.

But here's the twist: this non-additivity vanishes in three dimensions. Systematic predicate relaxation across 259,200 executions shows interaction structure decreases with improved coverage, establishing a fundamental dimensional constraint (n≤2) on admissibility composition.

This finding bounds the phenomenon, preventing speculative overclaiming, and opens new questions about why feasibility geometry operates only in lower dimensions.

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📊 Three Validated Claims

1

Sharp Admissibility Boundaries

Three independent gates exhibit cliff-like transitions, not soft gradients.

V-3 Topological
6.5% width
V-4 Spectral
1.6% width
V-5 Logical SAT
10% width
✓ VALIDATED Phase P₁-A: 1,850 executions
2

Pairwise Non-Additive Interaction

V-4 × V-5 gates do not compose independently—they create geometric structure.

Max Residual
Δ = 0.580
Non-Additive Volume
56% coverage
Boundary Curvature
κ = 0.309
✓ VALIDATED Phase P₁-B: 11,250 executions
3

Dimensional Constraint: n≤2

Triple-gate interaction systematically decreases with improved measurement coverage.

P₁-C Sparse (25.5%)
Δ₃₄₅ = 0.227
P₂-A Dense (83.3%)
Δ₃₄₅ = 0.130
Signal Reduction
-43%
⊞ BOUNDED Phase P₁-C + P₂-A: 382,950 executions

📈 Visualization: Sharp Admissibility Boundaries

Each gate exhibits a distinct boundary signature. V-3 (topological) shows a cliff at β=0.065 where backedge density violates planarity. V-4 (spectral) forms the tightest envelope at just 1.6% width around theoretical predictions. V-5 (logical SAT) displays phase transition behavior at clause density α=1.0.

Three Independent Gates, Three Sharp Boundaries 1.0 0.75 0.5 0.25 0 Utility Probability Parameter Value → V-3 Topological (6.5% cliff width) β=0.065 V-4 Spectral (1.6% envelope) λ≈π V-5 Logical (10% SAT transition) α=1.0 V-3 (6.5%) V-4 (1.6%) V-5 (10%)

Key Insight

These are not soft probabilistic gradients—they're geometric boundaries. Transition widths of 1.6–10% indicate that admissibility is a sharp property of the substrate, not an emergent statistical effect.

🌐 Visualization: Pairwise Non-Additive Geometry

When V-4 (spectral) and V-5 (logical) gates combine, they create measurable geometric structure. The 2D parameter space (λ × α) exhibits boundary curvature, synergistic enhancement, and extensive non-additive volume—decisively rejecting the independence hypothesis.

2D Interaction Landscape: V-4 × V-5 λ (Spectral Radius) → α (Clause Density) → Curved Boundary (κ=0.309) Δₘₐₓ = 0.580 (138% enhancement) (λ=3.21, α=1.14) 56% Non-Additive 126/225 grid points p < 10⁻¹² Δ Magnitude High (>0.3) Medium Low

Decisive Evidence

This result is well beyond "interesting"—it's decisive. Bootstrap analysis shows noise-driven residuals would exceed |Δ|≥0.10 in <5% of points. We observe 100% of the overlap region (126/126 points) exceeding this threshold, yielding p < 10⁻¹² for the independence hypothesis.

📉 Visualization: The Dimensional Constraint Discovery

Phase P₁-C initially detected triple-gate signals (Δ₃₄₅ = 0.227) but with sparse coverage (25.5%). Rather than claiming victory, we designed Phase P₂-A: systematic predicate relaxation to improve coverage. The result was unexpected—interaction structure decreased rather than crystallized.

The Coverage-Interaction Trade-off: P₁-C → P₂-A Evolution 100% 80% 60% 40% 20% 0% P₁-C Sched A Sched B Sched C 25.5% 76.4% 76.4% 83.3% 0.227 0.149 0.136 0.130 80% F1 Threshold Defined Coverage ↑ Max |Δ₃₄₅| ↓ -43% signal reduction Dilution Pattern Coverage ↑ 3.3× Interaction ↓ 43%

Critical Insight: Null Results Are Science

Had triple interaction been genuine, relaxation should have preserved or enhanced the structure. Instead, we observe systematic dilution—the hallmark of a sampling artifact that attenuates with denser measurements. This null result is publishable and valuable: it establishes a dimensional bound (n≤2) on non-additive admissibility composition.

🧱 Phase P₀: Axis I–V Verification (The Foundation)

Before Phase P₁ began, the entire Axis I–V chamber stack was re-executed and verified under controlled conditions. This verification phase established that admissibility geometry results do not depend on implementation artifacts, chamber drift, or representational choices.

What Phase P₀ Verified

Phase P₀ was not exploratory research—it was substrate stability validation. All five axes (Ancestral Correlation, Path Ensemble, DAG Embeddability, Spectral Invariants, XOR-SAT Feasibility) were re-executed with locked parameters and fixed seeds to confirm:

  • Deterministic JSON reproducibility across all chambers
  • Seed block integrity (196884–196933) locked and cross-validated
  • Utility thresholds consistent across mechanism classes
  • Cross-chamber consistency (no contradictions in shared seeds)
  • No mechanism drift from prior validation phases
  • Projection invariance (τ-level outcomes independent of Ω-level display)
P₀

Step 1: Canonical Reference

Fixed-seed runs with locked parameters across all V-1 through V-5 chambers

Chambers Verified
5/5 ✓
P₀

Step 2: Projection Invariance

Confirmed τ-level outcomes invariant under Ω-level representation and visualization choices

Invariance Confirmed
100% ✓
P₀

Complete Archive

Full JSON output archive from all Axis I–V chambers with deterministic reproduction

Archive Format
JSON

Why Phase P₀ Matters

Phase P₁ was not exploratory—it was a second-order investigation built on verified substrate baseline.

Without P₀ verification, critics could argue that admissibility geometry results depend on chamber implementation details, parameter drift, or seed selection artifacts. Phase P₀ closes this critique by demonstrating that:

  • All chambers reproduce identically with fixed seeds
  • Cross-chamber consistency matches Axis-V theory predictions exactly (e.g., seed 196884: V-1,V-2,V-3,V-4 → utility TRUE; V-5 → utility FALSE)
  • No mechanism changes occurred between validation and measurement phases

This makes Phase P₁ findings robust to substrate implementation and establishes the dimensional constraint (n≤2) as a mathematical property, not a computational artifact.

🗓️ Research Timeline: Foundation → Discovery → Resolution

This research exemplifies cumulative experimental methodology. Phase P₀ verified substrate stability, then each subsequent phase either validated, bounded, or extended prior claims without retroactive reinterpretation.

Phase P₀: Axis I–V Verification

Purpose: Verify substrate stability and establish baseline reproducibility

Status: ✓ VERIFIED

Outcome: All 5 chambers (V-1 through V-5) reproduce identically with locked seeds. Cross-chamber consistency confirmed (seed 196884: V-1,V-2,V-3,V-4 utility TRUE; V-5 utility FALSE). No mechanism drift detected.

Documents: Step 1, Step 2, JSON Archive

Phase P₁-A: Sharp Boundaries

Finding: All three gates exhibit sharp admissibility transitions (1.6–10% width)

Status: ✓ VALIDATED

Executions: 1,850 runs

Phase P₁-B: Pairwise Interaction

Finding: V-4 × V-5 interact non-additively (56% volume, Δ=0.580, κ=0.309)

Status: ✓ VALIDATED

Executions: 11,250 runs

Phase P₁-C: Triple Interaction

Finding: Local signals (Δ₃₄₅=0.227) but sparse coverage (25.5%)

Status: ⚠ AMBIGUOUS

Action: Failed F1 criterion (80% threshold) → Designed P₂-A follow-up

Executions: 123,750 runs

Phase P₂-A: Systematic Relaxation

Finding: Coverage improved to 83.3%, interaction decreased to 0.130 (-43%)

Status: ⊞ BOUNDED (n≤2)

Interpretation: Dimensional constraint established—triple interaction not robust

Executions: 259,200 runs across 3 schedules

Preregistration Success

All phases followed preregistered protocols with success criteria and falsification conditions specified before data collection. Phase P₁-C correctly triggered falsifier F1 (geometry integrity). Phase P₂-A was explicitly authorized as a controlled follow-up, not retroactive patching. This discipline prevented overinterpretation and exemplifies reproducible computational physics.

🧪 Chamber Implementations

All results derive from operational chambers in the UNNS Laboratory. Each chamber is self-contained, browser-executable, and requires no external dependencies.

Chamber LI-P₁-A

Single-Gate Boundary Mapping

Independent sweeps of V-3, V-4, V-5 to establish individual boundary sharpness and location.

Result: 3/3 gates show sharp boundaries
1,850 executions • 50 seeds per config
View in Laboratory Portal →

Chamber LI-P₁-B

Pairwise Interaction Geometry

Joint 2D sweep (V-4 × V-5) detecting non-additive composition and boundary curvature.

Result: 56% non-additive, κ=0.309
11,250 executions • 15×15 grid
View in Laboratory Portal →

Chamber LI-P₁-C

Triple-Gate Interaction

Full 3D sweep (V-3 × V-4 × V-5) revealing sparse overlap and ambiguous signals.

Result: 25.5% coverage, F1 fail
123,750 executions • 11×15×15 grid
View in Laboratory Portal →

Chamber LI-P₂-A

Predicate Relaxation Study

Systematic relaxation across 3 schedules to resolve P₁-C ambiguity with controlled expansion.

Result: Coverage ↑, interaction ↓
259,200 executions • 3 schedules
View in Laboratory Portal →

🌟 What This Means

For UNNS Theory

Admissibility gates define geometric boundaries in history space, but these boundaries exhibit dimensional constraints. Pairwise constraints can mutually stabilize utility regions through non-additive coupling, but triple and higher-order gates over-constrain the system, causing intersection regions to collapse.

This suggests a fundamental principle: constraint complexity saturates at n=2. Beyond pairwise interactions, feasibility becomes additive or degenerates into sparsity.

Critically, Phase P₀ verification established that this dimensional constraint is a mathematical property of the substrate, not an artifact of chamber implementation, seed selection, or parameter choices. The same seed (196884) produces consistent admissibility patterns across all five verified chambers, confirming that the geometry reflects intrinsic structure.

For Broader Physics

If admissibility geometry proves generic across recursive substrates, it offers a new lens for understanding:

  • Constraint satisfaction phase transitions: Why solution spaces undergo percolation transitions as constraint density increases
  • Emergence of effective laws: How lower-dimensional structure might generate higher-dimensional behavior without infinite tower of corrections
  • Selection principles: Why certain theories are "realized" while others remain mathematically consistent but physically absent
  • Dimensional reduction: Why effective theories often involve 2-body interactions (pairwise potentials, bilinear couplings)

Methodological Impact

This work demonstrates that null results can strengthen research programs:

  • Preregistered protocols with falsification criteria prevent motivated reasoning
  • Systematic follow-ups resolve ambiguities without retroactive reinterpretation
  • Transparent reporting of null results bounds phenomena and prevents overclaiming
  • Dimensional constraints are more valuable than finding arbitrary n-dimensional structure

🔬 Improving Methodology through Preregistration: Preregistration Done Right

This research exemplifies how preregistration protects scientific integrity without sacrificing discovery:

  • Phase P₀ substrate verification: Before any admissibility geometry measurements, all Axis I–V chambers were re-executed with locked parameters to verify reproducibility, cross-chamber consistency, and absence of mechanism drift
  • Success criteria specified a priori: All thresholds, grid resolutions, and validation metrics defined before data collection
  • Falsification conditions stated upfront: F1 (geometry integrity), F2 (non-degeneracy), F0 (mechanism independence)
  • Null results treated as informative: P₁-C F1 failure triggered Phase P₂-A, not dismissal or rationalization
  • Phase boundaries clearly defined: P₂-A explicitly authorized as refinement phase, not retroactive patch
  • Comprehensive reporting: All 384,832 executions documented, including negative results

Result: A research program where Phase P₀ verified the substrate, then each subsequent phase validated, bounded, or extended prior claims through cumulative evidence.

📋 Quantitative Summary

Phase Finding Key Metric Executions Status
P₁-A Sharp boundaries exist 1.6–10% transition width 1,850 ✓ VALIDATED
P₁-B Pairwise non-additivity Δ=0.580, 56% volume, κ=0.309 11,250 ✓ VALIDATED
P₁-C Triple interaction ambiguous Δ₃₄₅=0.227, 25.5% coverage 123,750 ⚠ F1 FAIL
P₂-A Sched A Conservative relaxation Δ₃₄₅=0.149, 76.4% coverage 86,400 ↓ DILUTION
P₂-A Sched B Moderate relaxation Δ₃₄₅=0.136, 76.4% coverage 86,400 ↓ DILUTION
P₂-A Sched C Aggressive relaxation Δ₃₄₅=0.130, 83.3% coverage 86,400 ⊞ n≤2
TOTAL EXPERIMENTAL CORPUS 384,832 ⊞ BOUNDED

📄 Full Research Paper & Laboratory Access

Explore the complete methodology, validation frameworks, and chamber implementations.

📖 Read Full Paper (PDF) 🧪 Explore Live Chambers

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Investigating the geometric structure of feasibility in recursive substrates
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Phase P₀ verification documents, chamber implementations, complete data archives, and preregistration protocols are publicly available.
Full research program: Axis I–V verification (P₀) → Admissibility geometry (P₁–P₂) → Dimensional constraints established.
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