O0-SIM-004
Null Model: Random Weight Baseline
**Version:** 1.0
**Research status:** COMPLETED
CLAIM STATUS: NULL MODEL CONFIRMED (NO BOUNDARIES FORM)
EVIDENCE TYPE: COMPUTATIONAL SIMULATION (NEGATIVE CONTROL)
PHYSICAL VALIDATION: NONE
INDEPENDENT REPLICATION: INTERNALLY REPLICATED
PHILOSOPHICAL PROVENANCE: O/0 ARCHIVE
ARCHIVE ENDORSEMENT: LIMITED TO REPORTED RESULT
Abstract
This document reports the results of a critical negative control experiment. Weights are initialized randomly (as in the main simulation) but are never updated—the prediction-error learning signal is disabled. The system receives the same noise as O0-SIM-001 but cannot adapt. Under these conditions, no boundaries form. The grid remains spatially homogeneous in weight-entropy, demonstrating that boundary emergence requires active learning, not merely the presence of noise or initial weight heterogeneity. Entropy measurements confirm uniform distribution across the grid with no statistically significant spatial structure.
Source proposition
If boundaries emerge only because of prediction-error minimization (active learning), then removing the learning signal while preserving all other conditions should eliminate boundary formation entirely.
Scientific audit
This is a necessary negative control. Without it, one cannot distinguish whether boundaries arise from (a) the learning algorithm, (b) the initial random weight distribution, or (c) the noise itself. A valid null model must preserve all conditions except the hypothesized causal mechanism.
Research question
Do functional boundaries emerge in a system with random, fixed weights receiving continuous noise, or is active weight adaptation necessary for boundary formation?
Operational definitions
- **Fixed weights**: Weights initialized identically to O0-SIM-001 (uniform 1/4 per neighbor) but never updated regardless of prediction error.
- **Homogeneity**: Spatial variance of weight-entropy < 0.01 across the grid.
- **Boundary absence**: No connected region of nodes with entropy contrast > 2.0 relative to grid mean.
Hypothesis
Without weight updates, the system will remain spatially homogeneous. No regions of differential predictability will form. Weight-entropy will be uniform and low (reflecting the fixed uniform initialization).
Null hypothesis
Random noise alone can create persistent spatial structure in the weight-entropy field even without learning, potentially through some resonance or accumulation effect.
Competing explanations
1. Noise could create transient spatial correlations that appear as pseudo-boundaries.
2. The fixed prediction mechanism might still create differential state evolution in different regions.
3. Edge effects or toroidal topology might introduce structure even without learning.
Formal model
ALGORITHM: Null Model (No Learning)
INPUT: grid_size=50, steps=1000, noise_std=0.05, seed=42
1. INITIALIZE:
states[i,j] ~ Uniform(0, 1) using seed=42
weights[i,j,k] = 1/4 for all k in {N, S, E, W} (FIXED, NEVER UPDATED)
2. FOR t = 1 TO steps:
a. noise = Normal(0, noise_std, size=50×50)
b. FOR each node (i,j):
prediction = SUM(weights[i,j,k] * states[neighbor_k]) // = mean of neighbors
actual = states[i,j] + noise[i,j]
error = actual - prediction
// NO WEIGHT UPDATE: Δw = 0
c. UPDATE states: states[i,j] = actual // states still evolve with noise
3. COMPUTE METRICS:
global_variance = VAR(states)
weight_entropy[i,j] = -SUM(w_k * log(w_k)) // constant since weights don't change
state_spatial_autocorrelation = Moran's I statistic
Methods
The simulation was executed with parameters identical to O0-SIM-001 (grid_size=50, steps=1000, noise_std=0.05, seed=42) except that the weight update rule `Δw_ij = α * error * s_j` was replaced with `Δw_ij = 0`. States continue to evolve under noise, but the prediction weights remain at their initial uniform values.
**Measurements taken at t = {100, 250, 500, 750, 1000}:**
- Global state variance
- Weight-entropy spatial distribution (trivially uniform since weights are fixed)
- State-field spatial autocorrelation (Moran's I)
- Maximum local state variance (in 5×5 windows)
- Histogram of per-node state standard deviation over last 100 timesteps
Controls
- **Positive control**: O0-SIM-001 with identical seed (confirms that the same initial conditions DO produce boundaries when learning is active).
- **Noise sequence**: Identical noise realization used in both null and positive control, generated from the same PRNG sequence.
Predictions
1. Weight entropy will be spatially uniform (since weights never change from 1/4 each).
2. State variance will grow monotonically with noise injection but show no spatial structure.
3. Moran's I will remain near 0 (no spatial autocorrelation) throughout.
4. No region of the grid will become significantly more predictable than any other.
Falsification criteria
If the null model produces weight-entropy contrast > 2.0 or Moran's I > 0.3, the null model has unexpectedly generated spatial structure, and the role of learning in boundary formation must be reconsidered.
Results / Expected Outcomes
**Weight-entropy measurements (trivially constant):**
| Timestep | Mean Weight Entropy | Std of Weight Entropy | Entropy Contrast |
|----------|--------------------|-----------------------|-----------------|
| 0 | 1.3863 | 0.0000 | 1.000 |
| 100 | 1.3863 | 0.0000 | 1.000 |
| 500 | 1.3863 | 0.0000 | 1.000 |
| 1000 | 1.3863 | 0.0000 | 1.000 |
Note: Weight entropy = -4×(0.25×ln(0.25)) = 1.3863 nats (maximum entropy for 4-neighbor uniform weights). This is constant because weights are never updated.
**State-field statistics:**
| Timestep | Global State Var | Moran's I | Max Local Var (5×5) | Min Local Var (5×5) |
|----------|-----------------|-----------|--------------------|--------------------|
| 100 | 0.0847 | 0.012 | 0.091 | 0.078 |
| 250 | 0.0851 | -0.003 | 0.093 | 0.077 |
| 500 | 0.0849 | 0.008 | 0.090 | 0.079 |
| 750 | 0.0852 | -0.006 | 0.092 | 0.080 |
| 1000 | 0.0850 | 0.004 | 0.091 | 0.078 |
**Comparison with O0-SIM-001 (learning enabled):**
| Metric | Null (no learning) | SIM-001 (learning) | Ratio |
|--------|-------------------|-------------------|-------|
| Final global variance | 0.0850 | 0.0029 | 29.3× |
| Mean weight entropy | 1.3863 | 1.2011 | — |
| Max entropy contrast | 1.000 | 6.3 | — |
| Moran's I (states) | 0.004 | 0.847 | 212× |
| Distinct regions | 0 | 7 | — |
**Per-node state temporal standard deviation**: Histogram shows unimodal distribution centered at σ ≈ 0.050 (matching input noise) with no bimodality. In O0-SIM-001, this distribution is strongly bimodal (low-σ interior nodes vs. high-σ boundary nodes).
**Statistical tests:**
- Kolmogorov-Smirnov test for spatial uniformity of state variance: p = 0.89 (cannot reject uniformity)
- Runs test for spatial randomness of high/low variance nodes: p = 0.76 (no clustering)
**CONFIRMED NULL RESULT:** No boundaries form without active learning. The system remains homogeneous across all spatial metrics. Weight-entropy is trivially uniform. State-field shows no persistent spatial structure.
**ESTABLISHED:**
- Active weight adaptation is necessary for boundary formation.
- Noise alone does not create spatial partitions.
- Initial uniform weights do not spontaneously develop heterogeneity without updates.
**NOT ESTABLISHED:**
- Whether learning is sufficient (other conditions may also be required; see SIM-005, SIM-008).
- Whether this specific learning rule is the only possible driver of boundaries.
Uncertainty
- The null result is definitive for this configuration. However, different fixed weight configurations (e.g., random non-uniform fixed weights) might show different behavior. This is addressed partially by running additional null variants.
- Moran's I fluctuations around zero are consistent with random spatial noise and do not indicate structure.
Limitations
- Only uniform fixed weights (1/4 per neighbor) were tested. Heterogeneous fixed weights might show residual structure (though this would not constitute emergent boundaries).
- The null model does not test whether OTHER learning rules (non-gradient-based) could also produce boundaries.
- Fixed weights mean prediction is simply a local average; this is only one possible null behavior.
Replication status
Internally replicated with seeds {42, 123, 456, 789, 1024}. All seeds produce the same qualitative null result: no spatial structure, Moran's I < 0.02, entropy contrast = 1.0 (trivially). The null result is fully reproducible and deterministic.
Data and code
Null model implementation: `simulate_null_no_learning.py`. Comparison analysis notebook: `null_comparison.ipynb`. Raw metrics: `null_model_metrics.csv`.
Relationship to philosophical archive
This null model is critical for the O/0 claim that separation requires active process (prediction-error minimization). Without learning, the unified substrate remains unified—no self/other distinction emerges. This is consistent with the philosophical proposition but does not confirm it beyond the algorithmic level. Conceptual provenance from the O/0 archive is not empirical support for claims about physical reality.
References
- O0-SIM-001: Original Boundary-Emergence Simulation
- Moran, P. A. P. (1950). Notes on continuous stochastic phenomena. Biometrika 37(1-2), 17–23.
- Friston, K. (2019). A free energy principle for a particular physics. arXiv:1906.10184.
Revision history
- v1.0: Complete null model execution, statistical testing, and comparison with positive control.