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.
Orientability is equivalent to a nowhere-vanishing top form
Statement
Assume . A smooth manifold is orientable if and only if it has a nowhere-vanishing smooth top-degree form.
Facts & Assumptions
Given: and a smooth manifold.
Proof
A nonzero top form selects the determinant ray on which it is positive, producing an orientation.
Conversely choose positive local top forms for an orientation and multiply them by a subordinate partition of unity. At every point all nonzero summands lie in the same positive ray, so their sum is nonzero and is a global top form.
Depends on
Used by
Nothing in the library uses this result yet.
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
- Ioan Mărcuț, Manifolds (2017 lecture notes), §§14.5, 15.1 (standard reference, not scraped)
- Will Merry, Differential Geometry (2021), Lecture 24 (standard reference, not scraped)