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.
Thom spaces of zero and trivial bundles
Statement
Naturally in , and the trivial disk/sphere pair is .
Facts & Assumptions
Given: A space , the zero bundle, and the product bundle with its standard Euclidean metric.
Disk, sphere, and Thom spaces of a metric vector bundle defines the disk, sphere, and based quotient, including the empty-sphere convention in rank zero.
Proof
In rank zero each fiber is the singleton zero vector, so [F1] gives and . By the based-quotient convention, .
For with the product metric, the norm depends only on the second coordinate, hence . Collapsing the second subspace gives .
By definition . Every displayed map sends by the identity formula and therefore commutes with pullback along a map . For both sides are the one-point based space; for , and step 1.2 reduces to step 1.1; for the boundary consists of the two endpoints. Zero and unit radii and the quotient basepoint are preserved, and no choice is used.