Alphabeta Math
DefinitionDefinition: AI-adaptedProof: Not applicablePipeline-generatedjudge pass (gpt-5.6-terra)
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.

Fine measures, strong compactness and supercompactness

Definition

Work in ZFC, with The Axiom of Choice for cardinal sizes, and fix a regular uncountable cardinal kappa as in Cofinality cf(α), and regular and singular cardinals. For a cardinal lambda>=kappa put

Pκ(λ)={xλ:x<κ}.

This is a set by Separation from the power set, and contains empty. A proper kappa-complete ultrafilter U on this index set, in the sense of Complete ultrafilters and measurable cardinals, is fine if {x:αx}U for every alpha<lambda. It is normal if whenever S belongs to U and f:Sλ satisfies f(x) in x for every x in S, some fibre of f belongs to U. In particular such a domain cannot contain the empty index x. Fineness alone does not assert normality.

The cardinal kappa is strongly compact if every proper kappa-complete filter on every set extends to a kappa-complete ultrafilter on that same set. It is lambda-supercompact if P_kappa(lambda) carries a normal fine kappa-complete ultrafilter; it is supercompact if it is lambda-supercompact for every cardinal lambda>=kappa. These are existence properties, not assertions that such cardinals or measures exist. Lambda=kappa is allowed. No comparison between strong compactness and supercompactness is assumed in this definition.

Depends on

Used by

Dependency tree · two levels

11 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