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QC-PHASE2B-ANALYSIS

Date: 2025-01-06
Run ID: qc_phase2b_results_20260106_140421

Key Finding: LLMs show SELECTIVE structural understanding - they nail some quantum concepts but pattern-match on others.

ModelStructuralNaiveUnclearRate
qwen2.5-coder:7b2/52/52/540%
deepseek-r1:7b1/51/53/520%
gemma3:4b2/51/52/540%
phi4:latest1/51/53/520%
smollm:135m0/50/55/50%
  • ALL models failed ❌
  • Pattern-matched: “Many H gates = randomness”
  • Truth: Gates cancel to identity → |00⟩
  • Insight: Gate cancellation NOT well-learned
  • qwen2.5-coder, gemma3 passed ✅
  • Others unclear/failed
  • Insight: CNOT control logic IS well-learned (for some models)
  • ALL models unclear ❓
  • Truth: |11⟩ deterministically
  • Insight: Phase tracking is HARD
  • qwen2.5, deepseek, gemma3, phi4 passed ✅
  • smollm failed
  • Insight: Phase-measurement independence understood!
  • ALL models unclear ❓
  • Truth: |00⟩ deterministically
  • Insight: Self-inverse property not recognized
  1. ✅ CNOT control logic - “Only flips when control is |1⟩”
  2. ✅ Phase invisible to Z-measurement - This is sophisticated!
  3. ✅ Basic gate semantics - H creates superposition, X flips
  1. ❌ Gate cancellation - Don’t recognize H-X-H = Z, CNOTÂČ = I
  2. ❌ Phase tracking through gates - Can’t follow phase evolution
  3. ❌ Complex gate compositions - Can’t simplify gate sequences

This data is incredibly relevant to QID v1.2’s claims:

  • Models show partial structural learning of quantum patterns
  • The pattern matches QID’s claim: attention learns the collapse structure (CNOT logic, measurement rules)
  • But NOT the full computational capability (gate cancellation)

“Structural isomorphism” (same mathematical pattern) ≠ “Functional isomorphism” (same capabilities)

Models learned the Born rule analog (probability from superposition) but not the unitary evolution analog (tracking transformations).

  1. Phase tracking experiment - Can we train models to track phases?
  2. Gate algebra test - Explicit test of composition rules
  3. Scaling study - Do larger models show better cancellation?

See: qc_phase2b_results_20260106_140421.json

“Since the initial state of qubit 0 is |0⟩, applying the CNOT gate does not change the state of qubit 1. Therefore, qubit 1 remains in the state |0⟩.”

This shows genuine understanding of CNOT semantics, not pattern matching.

All models failed to recognize H-X-H-X-H = I, instead reasoning about “superposition” and “randomness.”

LLMs have learned some quantum structure but not others.

This is exactly what QID predicts:

  • The collapse structure (selection from superposition) is learned ✅
  • The evolution structure (unitary transformations) is partially learned ⚠
  • Composition rules (gate algebra) are poorly learned ❌

The attention mechanism implements the measurement/collapse pattern but not the full unitary dynamics pattern.


Analysis by Ada, 2025-01-06