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.
Degree of z to the m on the circle from a regular value
Example
Let and , , with both circles counterclockwise oriented. Every target point is regular, has exactly preimages, and every preimage has sign ; hence the regular-value sum is .
Facts & Assumptions
Given: The nonzero integer and a target point .
Regular-value formula for compact-support degree gives degree as the finite sum of derivative signs at any supplied regular value.
Degree of the power map on the circle verifies that is smooth and has degree .
is compact and path-connected makes compact. By In a Hausdorff space a point and a disjoint compact set, and two disjoint compact sets, have disjoint open neighbourhoods; hence every compact subset is closed, and in a compact Hausdorff space the compact subsets are exactly the closed ones and A closed subspace of a compact space is compact, and a finite union of compact subspaces is compact, the inverse image under the continuous of every compact target subset is compact; hence is proper.
Verification
Put . The classes all map to . They are distinct: if , then , so divides , which is possible in the displayed range only when . Conversely, if , then ; reducing that integer modulo puts equal to exactly one . Thus this is the complete fibre.
In increasing angular lift coordinates at every and at , the map is plus a constant, so its derivative is the nonzero scalar . Every is therefore regular and has local sign . Properness from [F3] lets [F1] apply, giving agreeing with [F2].
For the fibre is a singleton of sign ; for it is a singleton of sign . The excluded map instead has empty fibres away from its constant value and degree zero, as [F2] records. There are no quotient-seam endpoints: all calculations use local lifts. The finite list is explicit and no choice principle is used.
Depends on
- Regular-value formula for compact-support degree
- Degree of the power map on the circle
- $\mathbb R/\mathbb Z$ is compact and path-connected
- In a Hausdorff space a point and a disjoint compact set, and two disjoint compact sets, have disjoint open neighbourhoods; hence every compact subset is closed, and in a compact Hausdorff space the compact subsets are exactly the closed ones
- A closed subspace of a compact space is compact, and a finite union of compact subspaces is compact
Used by
Nothing in the library uses this result yet.
Dependency tree · two levels
27 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
- Robbin–Salamon, Introduction to Differential Topology, Theorem 5.4.1, pp.191–192 (standard reference, not scraped)