Alphabeta Math
DefinitionDefinition: Literature-sourcedProof: Not applicableSession-authored (Fable 5 assisted)judge pass (deepseek-v4-pro + claude-opus-5[1m])audited 2026-08-24
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 rank of a derivative and constant-rank Euclidean maps

Definition

Let m,n1, let URm be open, and let f:URn be C1 (Ck Euclidean maps and diffeomorphisms). The rank of f at aU is rankaf:=rankDf(a), where rank is the dimension of the image (Rank and nullity of a linear map with finite-dimensional domain). In the standard bases, this is also the rank of the Jacobian matrix Jf(a) (The Jacobian matrix of partial derivatives and the gradient in the scalar-valued case).

For SU and 0rmin{m,n}, the map f has constant rank r on S when rankDf(x)=r for every xS. On the empty set this condition is vacuous, so it may hold for more than one r; every assertion that needs a determined rank will assume S is nonempty or specify r.

Depends on

Used by

Dependency tree · two levels

15 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