Alphabeta Math
TheoremStatement: Literature-sourcedProof: AI-adaptedPipeline-generatedjudge pass (gpt-5.6-terra)audited 2026-09-14
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.

The basic Fraenkel model

Statement

With countably infinite atoms, the full permutation group and finite supports yield a ZFA model in which every atom subset is finite or cofinite. The atom set is infinite, admits no injection from ω, is not well-orderable, and AC fails.

Facts & Assumptions

Given: An ambient ZFA+AC model with countably infinite atom set A, full permutation group, and finite-support filter.

[F2]

Dedekind infinitude is equivalent to a countable subset relates injections from ω to Dedekind infinitude without AC.

[F3]

The well-ordering theorem gives AC implies well-orderability.

Proof

1.1

Let BA in the model and let finite E support it. If two atoms a,bE had different membership in B, their transposition would fix E but move B. Thus either no atom outside E lies in B, making B finite, or every atom outside E lies in B, making it cofinite.

F1
2.1

The set A is infinite because every ground finite subset omits an atom. If f:ωA were injective in the model, the even-indexed range would be infinite and its complement would contain the infinite odd-indexed range, contradicting step 1.1. Hence there is no such injection, in agreement with F2.

F2step 1.1
3.1

If a well-order < of A had finite support E, the nonempty invariant set AE would have a least member a. Choose bE{a} and transpose a,b. The transposition fixes < and E, so must send its uniquely least outside-E member to itself, but sends a to b, contradiction. Thus A is not well-orderable. F3 now shows by contraposition that AC fails in the permutation model. This reductive use of AC is the only choice dependence of the conclusion.

F3

Depends on

Used by

Dependency tree · two levels

16 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