A universal group of type F∞

OpenAI

OpenAI claims a group of type F∞ containing every finitely presented group. Its finitely generated subgroups, up to isomorphism, are exactly the finitely generated recursively presented groups.

Sources for this record

What was already known

Higman constructed a universal finitely presented group and characterized its finitely generated recursively presented subgroups. Type F∞ adds finite skeleta in every dimension.

AI involvement AI-led

OpenAI credits its internal model with the mathematical manuscript. Staff organized the release; no separate human construction or completed human review is identified.

The model-produced manuscript and OpenAI authorship document central AI work; the released account does not establish autonomy from all human mathematical guidance.

Importance Notable

The construction would strengthen Higman’s universal embedding result with higher-dimensional finiteness.

Limitations

The companion simple-overgroup and Boone–Higman statements are separate claims. The released formalization checks part of the construction; the full universal embedding statement has no documented complete check.

Technical verification Partial

The published Lean declaration proves existence of a type-F∞ group embedding every finitely presented group. It does not itself state the manuscript's additional exact classification of finitely generated subgroups. The source does not document an independent imported-axiom audit.

Formal checking

Published Lean theorem in OAI/GroupTheory/UniversalGroup/Main.lean; subgroup-classification clause absent from this declaration

Checker
OpenAI's reported Lean development
Scope
OAI.UniversalFInfinity.universal_group_of_type_FInfinity: one type-F∞ group embeds every finitely presented group
Basis
Reported by the linked checker
Evidence source

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

Human understanding Few

Default for missing evidence: no named human explains the model's universal-group construction or proof mechanism.

Correction and publication history

2026-10-18 · publication

The construction would strengthen Higman’s universal embedding result with higher-dimensional finiteness.

Read this published revision