OpenAI reports a boundary obstruction to four-dimensional disk embedding

A compact oriented smooth four-manifold contains finitely many immersed disk maps with framed algebraic dual spheres whose embedded boundary circles bound no pairwise disjoint proper locally flat disks, even without prescribed output homotopy classes or framings.

Sources for this record

What was already known

Freedman’s simply connected disk-embedding methods and Freedman–Quinn’s good-group framework gave positive cases. The unrestricted disk-embedding conjecture asked for the conclusion without a fundamental-group condition.

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

Disproves unrestricted four-dimensional disk embedding and shows that the free group on two generators is not good in the Freedman–Quinn sense.

Limitations

The obstruction concerns the specified boundary link and all possible locally flat fillings; the input has framed algebraic duals.

Technical verification Reported

Reported is the default when evidence for a higher level is insufficient. The OpenAI-authored manuscript reports and argues the result, but the reviewed sources do not document a completed check of the full assessed claim.

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, and prior-work review for non-notifying local inclusion; technical verification remains Reported.

Read this published revision