χR(∣qubit_H⟩⊗5) ≤ 6

H-type orbit, qubit.

Participate

Run it yourself, or point a coding agent at it.

git clone https://github.com/unitaryfoundation/stabrank
cd stabrank
# describe your decomposition in bounds/mybound.json
make fit BOUND=bounds/mybound.json ARGS=--write
make verify BOUND=bounds/mybound.json

fit solves for the exact coefficients, or tells you no exact combination of your terms reproduces the target. verify rebuilds the identity in exact arithmetic. If it passes, open a pull request adding the file and the leaderboard picks it up on the next build.

A bound the pipeline cannot check is recorded as cited and never takes a record.

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Verification

lean   qubit_h_m5_stabRankP_le_six in LeanProofs.QubitHM5StabRank, machine-checked by Lean

Implied per-copy exponent γ ≤ 0.5170 against a published 0.3962, no improvement.

Lean proof

This bound is backed by a machine-checked theorem: qubit_h_m5_stabRankP_le_six in LeanProofs.QubitHM5StabRank. The recorded lake build confirms it compiles.

Compute

1 run; 0.02 CPU-hours; 0.02 h wall-clock; on Apple silicon laptop, 8 annealing chains.

Notes

The five-copy value of Bravyi, Smith, and Smolin, found there by Monte Carlo and conjectured optimal. Witness found here by the package's annealer (search_decomposition.py, target qubit_real, seed 1, starting rank 6, one run of 8 chains) and verified in exact arithmetic. Whether rank 5 is possible at m=5 is open; the rank-3 exclusion at m=4 and projection monotonicity give χ ≥ 4 here. Now at the lean tier: qubit_h_m5_stabRankP_le_six in LeanProofs.QubitHM5StabRank proves stabRankP 2 |qubitH⟩⊗5 ≤ 6 against IsStabP 2 from this witness, the pointwise identity being decided by the kernel on integer coordinate vectors (see lean_proofs/LeanProofs/Stabilizer/Reflect.lean).

Attribution

Bravyi, Smith, and Smolin · arXiv:1506.01396 · literature

Submission

JSON
{
  "schema_version": "0.1",
  "orbit": "qubit_H",
  "m": 5,
  "direction": "upper",
  "rank": 6,
  "provenance": {
    "author": "Bravyi, Smith, and Smolin",
    "reference": "arXiv:1506.01396",
    "method": "literature",
    "date": "2015-06-03",
    "github": [],
    "compute": {
      "cpu_hours": 0.02,
      "wall_clock_hours": 0.02,
      "runs": 1,
      "hardware": "Apple silicon laptop, 8 annealing chains"
    }
  },
  "notes": "The five-copy value of Bravyi, Smith, and Smolin, found there by Monte Carlo and conjectured optimal. Witness found here by the package's annealer (search_decomposition.py, target qubit_real, seed 1, starting rank 6, one run of 8 chains) and verified in exact arithmetic. Whether rank 5 is possible at m=5 is open; the rank-3 exclusion at m=4 and projection monotonicity give chi >= 4 here. Now at the lean tier: qubit_h_m5_stabRankP_le_six in LeanProofs.QubitHM5StabRank proves stabRankP 2 |qubit_H>^5 <= 6 against IsStabP 2 from this witness, the pointwise identity being decided by the kernel on integer coordinate vectors (see lean_proofs/LeanProofs/Stabilizer/Reflect.lean).",
  "lean": {
    "module": "LeanProofs.QubitHM5StabRank",
    "theorem": "qubit_h_m5_stabRankP_le_six"
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}