χR(∣T3⟩⊗4) ≤ 9

T₃ orbit, qutrit.

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   t3_m4_stabRankP_le_nine in LeanProofs.T3M4StabRank, machine-checked by Lean

Implied per-copy exponent γ ≤ 0.5000 against a published 0.5000, no improvement.

Lean proof

This bound is backed by a machine-checked theorem: t3_m4_stabRankP_le_nine in LeanProofs.T3M4StabRank. The recorded lake build confirms it compiles.

Notes

nine-term product witness from the m=2 carry decomposition Witness: the nine products vs ⊗ vt of the m=2 carry blocks, verified here in exact arithmetic. Now at the lean tier: t3_m4_stabRankP_le_nine in LeanProofs.T3M4StabRank proves stabRankP 3 |T3⟩⊗4 ≤ 9 against IsStabP 3 from this witness, the pointwise identity being decided by the kernel on integer coordinate vectors (see lean_proofs/LeanProofs/Stabilizer/Reflect.lean).

Attribution

Labib and Russo · arXiv:2605.28586 · literature

Submission

JSON
{
  "schema_version": "0.1",
  "orbit": "T3",
  "m": 4,
  "direction": "upper",
  "rank": 9,
  "provenance": {
    "author": "Labib and Russo",
    "reference": "arXiv:2605.28586",
    "method": "literature",
    "date": "2026-05-27",
    "github": [
      "FarLab",
      "vprusso"
    ]
  },
  "notes": "nine-term product witness from the m=2 carry decomposition Witness: the nine products v_s (x) v_t of the m=2 carry blocks, verified here in exact arithmetic. Now at the lean tier: t3_m4_stabRankP_le_nine in LeanProofs.T3M4StabRank proves stabRankP 3 |T3>^4 <= 9 against IsStabP 3 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.T3M4StabRank",
    "theorem": "t3_m4_stabRankP_le_nine"
  },
  "witness": {
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    "coeffs": [
      "1/3",
      "exp(2*I*pi/9)/3",
      "exp(4*I*pi/9)/3",
      "exp(2*I*pi/9)/3",
      "exp(4*I*pi/9)/3",
      "exp(2*I*pi/3)/3",
      "exp(4*I*pi/9)/3",
      "exp(2*I*pi/3)/3",
      "exp(8*I*pi/9)/3"
    ]
  }
}