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PropositionStatement: Literature-sourcedProof: AI-adaptedPipeline-generatedprecheck passjudge pass (gpt-5.6-terra)audited 2026-09-14
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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 B, Th⁡(0B)=B+;Th⁡(B×Rn)=B+∧Sn=ΣnB+, and the trivial disk/sphere pair is (B×Dn,B×Sn−1).

Facts & Assumptions

Given: A space B, the zero bundle, and the product bundle with its standard Euclidean metric.

[F1]

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

technique · calculate the defining quotients
1.1F1

In rank zero each fiber is the singleton zero vector, so [F1] gives D(0B)=B and S(0B)=∅. By the based-quotient convention, Th⁡(0B)=B+.

1.2F1

For B×Rn with the product metric, the norm depends only on the second coordinate, hence (D,S)=(B×Dn,B×Sn−1). Collapsing the second subspace gives (B×Dn)/(B×Sn−1)≅B+∧(Dn/Sn−1)=B+∧Sn.

2.1F1step 1.1step 1.2∎

By definition B+∧Sn=ΣnB+. Every displayed map sends (b,v) by the identity formula and therefore commutes with pullback along a map B′→B. For B=∅ both sides are the one-point based space; for n=0, S−1=∅ and step 1.2 reduces to step 1.1; for n=1 the boundary consists of the two endpoints. Zero and unit radii and the quotient basepoint are preserved, and no choice is used.

Depends on

Dependency tree · 2 levels

Sources