The Margulis-Platonov conjecture on normal subgroups of groups of rational points
Let be an absolutely almost simple simply connected algebraic group over a global field , let be the finite set of nonarchimedean places with , and let be the diagonal map. The Margulis-Platonov conjecture asserts that the compact anisotropic local groups account for all abstract normal subgroups: every noncentral normal subgroup of is for an open normal subgroup . It was known for isotropic groups, inner type A (Segev-Seitz, Rapinchuk-Segev-Seitz) and most anisotropic types, leaving anisotropic outer A, trialitarian and cases over number fields. Is every noncentral normal subgroup of of this form?
- Result
- Proved(see note)
- Status
- Candidate (review pending)
- AI contribution
- AI-discovered
- Method
- Argument
- Field
- Algebraic groups over global fields; arithmetic groups
- Posed by
- Grigory Margulis and Vladimir Platonov
- Year posed
- 1979
- Years open
- 47y
- Solved
- 2026-09-23
- Model
- Unreleased internal OpenAI model
- Vendor
- OpenAI
- Collaborators
- —
- Verification
- Unreviewed
- Publication
- Announced
- Collection
- OpenAI math release (October 2026), version adc7f12
- Significance
- 42 / 100
- Disclosed cost
- —
- Wikipedia
- No dedicated article
What was actually shown
Theorem 1.1 (number fields): for absolutely almost simple and simply connected over a number field , every noncentral normal subgroup equals for an open normal of ; when is empty, . With Rapinchuk's theorem it gives the congruence subgroup property for of positive Dirichlet density in the split places. The October 5 companion proves the same over every global function field, including characteristic two. It does not settle Serre's congruence subgroup conjecture for finite or arbitrary infinite .
What the AI did
The release README says the results were produced by an unreleased internal OpenAI model with a fixed procedure, on average about three hours of ChatGPT Pro thinking compute per result, and that some outputs build on earlier model results. This result is not among the README's exceptions (the Hodge conjecture for CM abelian varieties and the Re(s) > 11/12 zero-free region). The manuscript is authored 'OpenAI' and names no human author. The family has two manuscripts: number fields (September 23, 2026, this entry's principal) and global function fields including characteristic two (October 5, 2026).
Verification
No independent mathematician has checked this yet. Checked here: Theorem 1.1 of the number-field manuscript was read against the conjecture; it states the full conjecture over number fields with abstract normal subgroups and no finite-generation assumption, using the established reduction (cases already known) and supplying the remaining anisotropic outer A, trialitarian and cases. The function-field companion's abstract states the same over every global function field. Neither proof was refereed; there is no Lean formalization. The number-field paper relies on cited prior work (Segev-Seitz, Rapinchuk-Potapchik, Prasad-Rapinchuk's metaplectic kernel) as inputs.