OpenAI reports exponential semidefinite lift complexity for perfect matching

Every exact affine semidefinite lift of the perfect-matching polytope of the complete graph on n vertices has matrix size at least 2^{c n} for some absolute c>0 and all sufficiently large even n.

Sources for this record

What was already known

Unrestricted exponential lower bounds were known for linear extensions, and exponential semidefinite bounds were known under coordinate symmetry. Neither excludes an unrestricted small exact semidefinite lift.

AI involvement AI-led

OpenAI credits itself as manuscript author and states that its internal frontier model produced the results in this release. Individual human input is not detailed enough to establish task-only autonomy.

OpenAI is named as author on the manuscript, and its release attributes the results to an internal frontier model. The individual human input is not detailed enough to establish autonomy.

Importance Major

Rules out subexponential exact semidefinite formulations of the perfect-matching polytope without a symmetry assumption.

Limitations

The manuscript derives this from an exponential PSD-rank bound for positively shifted odd-cut slack matrices. The linked Lean scope establishes only a superpolynomial lower bound for exact affine semidefinite lifts; it does not certify the exponential rate or the positively shifted matrix theorem.

Technical verification Partial

OpenAI reports a Lean check of a narrower theorem, case, or component; the selected claim extends beyond that scope.

Formal checking

The pinned OpenAI Lean scope note verifies only this narrower statement, not the full selected claim.

Checker
OpenAI-reported Lean 4 / Comparator
Scope
For every fixed C>0, exact affine semidefinite lifts of the perfect-matching polytope eventually require matrix size greater than n^C.
Basis
Reported by the linked checker
Evidence source

Checking a formal statement does not establish that it matches the original problem.

Human understanding Few

Few is the default when evidence for a higher level is insufficient. No named person is documented as explaining the central argument for this assessed contribution.

Correction and publication history

2026-10-18 · publication

Primary manuscript, attribution, prior-work, and precise partial or mismatched Lean-scope review for non-notifying local inclusion.

Read this published revision