OpenAI reports an endpoint gradient bound for centered disk averages

For every real f in W¹,¹(R²), the centered-disk maximal function has a globally integrable weak gradient and satisfies ||∇Mf||₁ ≤ C||∇f||₁ for an absolute constant C.

Sources for this record

What was already known

Kinnunen established W¹,p control for p>1, while the strong maximal inequality used there fails at p=1; Hajłasz and Onninen asked whether the endpoint gradient estimate nevertheless holds.

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 Notable

Resolves the planar centered-disk case of a longstanding Sobolev endpoint question.

Limitations

The theorem concerns real W¹,¹ inputs in the plane and centered Euclidean disks; it does not assert global integrability of Mf or a BV extension.

Technical verification Formal (Lean 4)

OpenAI reports a Lean proof matching the selected claim.

Formal checking

The pinned Lean note covers local W¹,¹ regularity and the global L¹ weak-gradient bound for centered disk averages.

Checker
OpenAI-reported Lean 4 / Comparator
Scope
For every real f in W¹,¹(R²), the centered-disk maximal function has a globally integrable weak gradient and satisfies ||∇Mf||₁ ≤ C||∇f||₁ for an absolute constant 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 scoped checking review for non-notifying local inclusion.

Read this published revision