χR(∣qubit_H⟩⊗7) ≤ 9

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_m7_stabRankP_le_nine in LeanProofs.QubitHM7StabRank, machine-checked by Lean

Implied per-copy exponent γ ≤ 0.4528 against a published 0.3962, no improvement.

Lean proof

This bound is backed by a machine-checked theorem: qubit_h_m7_stabRankP_le_nine in LeanProofs.QubitHM7StabRank. The recorded lake build confirms it compiles.

Compute

1 run; 0.01 CPU-hours; 0.01 h wall-clock; on Apple silicon laptop, one core; direct construction, no search.

Notes

χ(|H⟩⊗7) ≤ 9 from the partial decomposition of Kissinger, van de Wetering, and Vilmart (arXiv:2202.09202, Section 4.2): |T⟩⊗5 = √ 2 (I ⊗ ⟨T|)|cat6⟩ has three terms, each a Clifford image of (stabilizer ⊗ |T⟩), so four T states are removed at a cost of three terms and χ(T^t) ≤ 3 χ(T^{t-4}). At t = 7 the leftover |T⟩ of each term joins the remaining |T⟩⊗2, and |T⟩⊗3 has rank 3, giving 3 x 3 = 9. Improves the 12 that QPG's table lists at seven copies. Witness built here by research/constructions/kvv_cat.py from the three cat_6 terms and the board's m=3 witness, and verified in exact arithmetic; exponent log_2(9)/7 = 0.4528. Now at the lean tier: qubit_h_m7_stabRankP_le_nine in LeanProofs.QubitHM7StabRank proves stabRankP 2 |qubitH⟩⊗7 ≤ 9 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

Kissinger, van de Wetering, and Vilmart · arXiv:2202.09202 · literature

Submission

JSON
{
  "schema_version": "0.1",
  "orbit": "qubit_H",
  "m": 7,
  "direction": "upper",
  "rank": 9,
  "provenance": {
    "author": "Kissinger, van de Wetering, and Vilmart",
    "reference": "arXiv:2202.09202",
    "method": "literature",
    "date": "2022-02-18",
    "github": [],
    "compute": {
      "cpu_hours": 0.01,
      "wall_clock_hours": 0.01,
      "runs": 1,
      "hardware": "Apple silicon laptop, one core; direct construction, no search"
    }
  },
  "notes": "chi(|H>^7) <= 9 from the partial decomposition of Kissinger, van de Wetering, and Vilmart (arXiv:2202.09202, Section 4.2): |T>^5 = sqrt 2 (I (x) <T|)|cat_6> has three terms, each a Clifford image of (stabilizer (x) |T>), so four T states are removed at a cost of three terms and chi(T^t) <= 3 chi(T^{t-4}). At t = 7 the leftover |T> of each term joins the remaining |T>^2, and |T>^3 has rank 3, giving 3 x 3 = 9. Improves the 12 that QPG's table lists at seven copies. Witness built here by research/constructions/kvv_cat.py from the three cat_6 terms and the board's m=3 witness, and verified in exact arithmetic; exponent log_2(9)/7 = 0.4528. Now at the lean tier: qubit_h_m7_stabRankP_le_nine in LeanProofs.QubitHM7StabRank proves stabRankP 2 |qubit_H>^7 <= 9 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).",
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    "theorem": "qubit_h_m7_stabRankP_le_nine"
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}