lean artifact · pending
Artifact ↗Kaplansky's direct finiteness conjecture
Theorem 1.1 (September 23): a finite field of characteristic two, a finitely presented group containing odd-order torsion, and with , . By Elek-Szabo, is not sofic. Companions: for a specified odd prime (the least prime factor of ), a field of order and a finitely generated group with torsion (September 26); and a finitely presented torsion-free group with a finite two-dimensional classifying complex and with , , (October 4). No counterexample in characteristic zero is possible, and none is claimed.
Exact FrontierDelta
Scope and record
Occurred: Sep 23, 2026
Delta type: SOURCE CLAIM
Assumptions: VibeMathed verification: lean-checked. Publication: announcement. AI contribution: ai-discovered. VibeMathed editorial classifications, scores, notes, relations, and dataset structure are CC BY 4.0. Source statements and linked content retain their own rights.
Canonical aliases: Kaplansky's direct finiteness conjecture · Kaplansky direct finiteness
Confidence: Not scored
Registry verification: lean checked · announcement · candidate
Attribution
VibeMathed
registry · event recorded by
Unreleased internal OpenAI model
model · ai model contributor · OpenAI
Artifacts and verifiers
lean artifact · pending
Artifact ↗lean artifact · pending
Artifact ↗lean artifact · pending
Artifact ↗Compute record
No linked compute attempts recorded.
Lineage and corrections
This event attributed to Unreleased internal OpenAI model
Input: Kaplansky counterexample in characteristic two evidence for this event
Companion: Counterexample in Odd Characteristic (Lean-checked automaton) evidence for this event
Comparator statement: KaplanskyFinitelyPresented.lean evidence for this event
Lean proof (OAI.KaplanskyCounterexample.finitelyPresented_counterexample) evidence for this event
VibeMathed record: Kaplansky's direct finiteness conjecture evidence for this event
Lean proof (OAI.OddKaplansky.main_theorem) evidence for this event
Comparator statement: KaplanskyDirectFiniteness.lean evidence for this event
Companion: A Torsion-Free Group Algebra That Is Not Directly Finite evidence for this event
Theorem 1.1 (September 23): a finite field of characteristic two, a finitely presented group containing odd-order torsion, and with , . By Elek-Szabo, is not sofic. Companions: for a specified odd prime (the least prime factor of ), a field of order and a finitely generated group with torsion (September 26); and a finitely presented torsion-free group with a finite two-dimensional classifying complex and with , , (October 4). No counterexample in characteristic zero is possible, and none is claimed. parent of this event
Kaplansky's direct finiteness conjecture parent of this event
Act on this frontier