χR(∣T3⟩⊗3) ≤ 8

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_m3_stabRankP_le_eight in LeanProofs.T3M3StabRank, machine-checked by Lean

Implied per-copy exponent γ ≤ 0.6309 against a published 0.5000, no improvement.

Lean proof

This bound is backed by a machine-checked theorem: t3_m3_stabRankP_le_eight in LeanProofs.T3M3StabRank. The recorded lake build confirms it compiles.

Notes

explicit eight-term witness; Kocia-Sarovar recorded this as 8? The eight terms are those of stabrank/examples/t3m3_rank8_certificate.py, found by annealing; here each is given in the flat-and-phase-form parametrisation and the identity is re-verified in exact arithmetic. Now at the lean tier: t3_m3_stabRankP_le_eight in LeanProofs.T3M3StabRank proves stabRankP 3 |T3⟩⊗3 ≤ 8 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": 3,
  "direction": "upper",
  "rank": 8,
  "provenance": {
    "author": "Labib and Russo",
    "reference": "arXiv:2605.28586",
    "method": "literature",
    "date": "2026-05-27",
    "github": [
      "FarLab",
      "vprusso"
    ]
  },
  "notes": "explicit eight-term witness; Kocia-Sarovar recorded this as 8? The eight terms are those of stabrank/examples/t3m3_rank8_certificate.py, found by annealing; here each is given in the flat-and-phase-form parametrisation and the identity is re-verified in exact arithmetic. Now at the lean tier: t3_m3_stabRankP_le_eight in LeanProofs.T3M3StabRank proves stabRankP 3 |T3>^3 <= 8 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.T3M3StabRank",
    "theorem": "t3_m3_stabRankP_le_eight"
  },
  "witness": {
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          0,
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        ],
        "l": [
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      }
    ],
    "coeffs": [
      "1/3 - exp(2*I*pi/3)/3",
      "-exp(2*I*pi/3)/3 + exp(8*I*pi/9)/3 - exp(-8*I*pi/9)/3 + exp(2*I*pi/9)/3",
      "2/3 + exp(2*I*pi/3)/3",
      "-2*exp(2*I*pi/9)/3 - exp(8*I*pi/9)/3",
      "-exp(2*I*pi/9)/3 + exp(-8*I*pi/9)/3 - exp(8*I*pi/9)/3 + exp(2*I*pi/3)/3",
      "1/3 - exp(2*I*pi/3)/3 + exp(2*I*pi/9)/3 + 2*exp(8*I*pi/9)/3",
      "-1/3 - exp(8*I*pi/9)/3 + exp(2*I*pi/9)/3 + exp(2*I*pi/3)/3",
      "-sqrt(3)*exp(2*I*pi/3)/3 + sqrt(3)*exp(8*I*pi/9)/3 + sqrt(3)*exp(4*I*pi/9)/3"
    ]
  }
}