Deciding finite-algebra congruence-lattice representability
Status OpenLLM status Open unverified
Top Open Problems unknownunknown Not reported cataloguedOpenOpenStatement
Definitions and mathematical statement
Statement recorded in the supplied source.
Does an algorithm exist that, on every order table of a finite nonempty lattice L, halts and determines whether L is isomorphic to Con(A) for some finite algebra A with arbitrary finitary operations?Short English statement
Does an algorithm exist that, on every order table of a finite nonempty lattice L, halts and determines whether L is isomorphic to Con(A) for some finite algebra A with arbitrary finitary operations?Sources
- S1 Original question source or mathematical context. http://www.openproblemgarden.org/op/finite_congruence_lattice_problem.
- S2 Original question source or mathematical context. http://en.wikipedia.org/wiki/Universal_algebra.
- S3 Original question source or mathematical context. http://en.wikipedia.org/wiki/Algebraic_lattice.
- S4 Original question source or mathematical context. http://www.openproblemgarden.org/op/which_lattices_occur_as_intervals_in_finite_groups.
- S5 Original question source or mathematical context. https://doi.org/10.4171/owr/2007/37.
- S6 Original question source or mathematical context. https://doi.org/10.4171/owr/2008/20.
- S7 OpenAI, manuscript citation page. Source of the formulation motivating this local problem. https://github.com/openai/math/blob/adc7f1241b42e322a6451854ab7e4b4c146bf78a/preprints/Finite-Congruence-Lattices-Characterization-and-Undecidability-September-24-2026/README.md.
Statement licence: CC-BY-4.0 · Source file
Contributions 1
OpenAI claim summary for Math-2513
The cited theorem explicitly forbids any total algorithm deciding finite-algebra representability from finite lattice tables. The formalization in lean/docs/206.md is only the graph criterion; it explicitly excludes undecidability. Within these assumptions, this is a claimed negative answer to the stated question.
Deciding finite-algebra congruence-lattice representability
OpenAI's claim
OpenAI presents a counterexample in the selected manuscript. A colored-graph criterion is claimed to characterize realizable finite congruence lattices, with an undecidable recognition problem; recognition of finite subgroup intervals is also claimed to be undecidable.Mathematical statement of the claimed result
Result 1.
For a nonempty finite lattice $L$, let $\mathcal R(L)$ mean that $L\cong\operatorname{Con}(A)$ for some finite algebra $A$. The claimed finite colored-graph criterion is equivalent to $\mathcal R(L)$, with a finite decision procedure once the candidate graph size is fixed. Nevertheless, \[ \text{no total algorithm decides }\mathcal R(L)\text{ from the order table of }L. \] The source also specifies a nonrepresentable lattice $L_0$ of least cardinality, with $|L_0|>7$ and every smaller finite lattice representable. Its group-interval assertion is \[ \text{no total algorithm decides }\exists G\text{ finite},\ H\le G:\ L\cong[H,G]. \] The undecidability theorem additionally rules out a total computable bound, depending only on $|L|$, on the smallest carrier size among representable lattices.Outline of the argument
Finite colored graphs encode the equivalences permitted by all operations of an algebra. Small witness configurations are assembled into lattice representation constraints, and arithmetic divisor obstructions rule out bounded algebraic realizations; a reduction turns the characterization into the claimed undecidability result.Formal verification
For family 206, the documented theorem identifies representability with a finite colored-graph witness. Undecidability, nonrepresentation, and subgroup-interval conclusions are not contained in that selected graph equivalence. The listed Comparator files areFiniteCongruenceGraph.lean. The inventory does not supply a named declaration for these Comparator entries. This site has not executed the Lean code. The scope descriptions do not certify the remaining manuscript arguments.Status caveat
OpenAI attributes these manuscripts to work by an internal model. Its release cautions that arguments without formalization can contain mistakes. This catalogue has not independently checked the proofs; the labels report the mathematical claims attributed to OpenAI.Sources
- OpenAI, Finite congruence lattices: characterization and undecidability, 2026-09-24; citation key
OAI:Finite-Congruence-Lattices-Characterization-and-Undecidability-September-24-2026. PDF (GitHub); PDF (direct); Manuscript page and citation; Latest version; Statement source: m:main; Statement source: n:undecidable. - Family 206: Lean scope.
- Comparator FiniteCongruenceGraph.json.
- Comparator FiniteCongruenceGraph.lean.
- OpenAI catalogue entry.