Alphabeta Math
TheoremStatement: Literature-sourcedProof: AI-adaptedPipeline-generatedprecheck passaudited 2026-09-06‡ rests on unproved material (inherited)
How statement and proof provenance work

The first chip identifies the source of the statement or construction; the second identifies the source of its local proof or verification.

  • Literature-sourced: the exact statement appears in a cited source; only wording and notation differ.
  • AI-adapted: a semantically identical restatement of literature-sourced material, modulo indexing, notation, and boundary cases adopted by the library.
  • AI-generated: a genuinely novel statement formulated by AI, with no source for the claim itself.

These labels describe origin, not correctness: citations and verification chips remain separate evidence.

‡ Rests on 3 statements not proved in this library, by way of the results it cites. This item cites no such statement directly; it depends on results that do. The unproved premises it inherits are ‡ Cohen's first model: an infinite Dedekind-finite set of reals, ‡ Sierpiński 1947: the generalised continuum hypothesis implies the Axiom of Choice and ‡ The continuum hypothesis and its generalisation are independent of ZFC. Each is recorded with a citation to the literature and is not established here, because the track that would prove it has not yet been developed in this library. Everything else in this proof is proved here.

The Kunneth sequence splits nonnaturally

Statement

Assume the Axiom of Choice. For free abelian complexes with finite diagonals, the Kunneth short exact sequence splits after choices, but no natural splitting is claimed.

Proof

Given: free abelian complexes satisfying the Kunneth hypotheses.

1.1

The Kunneth theorem for free abelian complexes in the cited source states that the natural short exact sequence is noncanonically split. Its proof chooses lifts in the free cycle-boundary presentations; it does not require the generally false assertion that each boundary subgroup is a direct summand of its chain group.

given
2.1

Choosing those lifts gives a section of the Kunneth quotient, while the source theorem makes no natural choice of them. Thus a splitting exists, but no natural splitting is claimed.

step 1.1construct∎

Depends on

Used by

Dependency tree · two levels

5 results within two dependency steps of this one, each drawn at its shortest distance from it. An arrow runs from a result to what uses it, so the chart reads left to right and ends at this result, which carries a heavier outline. Every node is a link to that result. Click elsewhere on the chart to enlarge it.

Sources