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.
Projective comparison maps are unique up to chain homotopy
Statement
Assume the Axiom of Dependent Choice.
Any two augmentation-preserving maps between projective resolutions lifting the same object morphism are chain-homotopic.
Facts & Assumptions
Given: Two augmentation-preserving maps between projective resolutions, lifting the same object morphism .
A partial comparison homotopy extends one degree at a time (Extending a partial comparison homotopy by one degree).
The maps and are comparison maps in the sense of Augmentation-preserving maps of projective resolutions.
Dependent choice licenses the countable successor-by-successor selection of compatible homotopy components (The axiom of dependent choice: a relation in which every element is related to something admits an -indexed chain).
Proof
Start at degree . Because and lift the same object map, [L1] produces . Every partial homotopy through degree extends one degree further by [L1], and the successive choices depend on the previously chosen components. Therefore [L3] produces a family in every degree.
By construction, the family satisfies the defining chain-homotopy equation in every degree. Therefore and are chain-homotopic.