Lech Multiplicity Conjecture for Flat Local Extensions
Status Open · unsolvedmath.comLLM status Open unverified
Top Open Problems unknownunknown Not reported cataloguedOpenOpenStatement
Definitions and mathematical statement
Shared notation.
$\mathbb N$, $\mathbb Z$, $\mathbb Q$, $\mathbb R$, and $\mathbb C$ denote the natural numbers, integers, rationals, reals, and complex numbers, respectively. All additional parameters and hypotheses are specified in the question.Statement recorded in the supplied source.
Lech's conjecture: if $(R,\mathfrak m)\to(S,\mathfrak n)$ is a flat local extension of Noetherian local rings, then $e(R)\leq e(S)$.Formulation references: [S1], [S2].
Short English statement
Lech's conjecture: if $(R,\mathfrak m)\to(S,\mathfrak n)$ is a flat local extension of Noetherian local rings, then $e(R)\leq e(S)$.Sources
- S1 ULAM.AI and the UnsolvedMath Contributors, UnsolvedMath: A Curated Collection of Open Mathematics Problems, record 30003303 (OWR-15178-003). Catalogue attribution under CC BY 4.0. https://huggingface.co/datasets/ulamai/UnsolvedMath.
- S2 Original problem formulation and mathematical context. https://doi.org/10.4171/owr/2016/57.
Statement licence: CC-BY-SA-4.0 · Source file
Contributions 1
OpenAI claim summary for Math-2428
Theorem 1.1 proves exactly the all-flat-local Hilbert–Samuel multiplicity comparison, without imposing a characteristic, ramification, dimension, or domain restriction. Within these assumptions, this is a claimed affirmative answer to the stated question.
Lech Multiplicity Conjecture for Flat Local Extensions
OpenAI's claim
OpenAI presents a proof in the selected manuscript. For a flat local map of nonzero Noetherian rings, the proposed inequality is $e(R)\leq e(S)$ without a dimension or characteristic restriction.Mathematical statement of the claimed result
Result 1.
For any flat local homomorphism $(R,\mathfrak m)\to(S,\mathfrak n)$ between nonzero Noetherian local rings, the claimed Hilbert--Samuel multiplicities satisfy \[ e_{\mathfrak m}(R)\le e_{\mathfrak n}(S). \] The theorem imposes no extra condition on residue fields, dimensions, or characteristic.Outline of the argument
The argument replaces unavailable Ulrich modules by short free complexes and a uniform estimate for their Euler lengths. Cohen factorization connects those estimates to multiplicity, while normalized-length algebras provide the parameter calculations in positive and mixed characteristic.Formal verification
For family 194, the Lean entry concerns positive-characteristic complete-domain Dutta multiplicity and its Frobenius limit; arbitrary-characteristic flat-local monotonicity is beyond that entry. The listed Comparator files areDuttaDomain.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, Lech's multiplicity conjecture, 2026-09-23; citation key
OAI:Lechs-multiplicity-conjecture-September-23-2026. PDF (GitHub); PDF (direct); Manuscript page and citation; Latest version; Statement source: thm:main. - Family 194: Lean scope.
- Comparator DuttaDomain.json.
- Comparator DuttaDomain.lean.
- OpenAI catalogue entry.