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.
Injective comparison maps exist
Statement
Assume the Axiom of Dependent Choice.
Let be a morphism, and let and be injective resolutions of and . Then there exists a coaugmentation-preserving cochain map extending .
Facts & Assumptions
Given: A morphism and injective resolutions of and of .
The opposite of an abelian category is abelian (The opposite of an abelian category is abelian).
An injective resolution is the cochain datum to be dualized (Injective resolutions in an abelian category).
Projective comparison maps exist (Projective comparison maps exist).
Proof
By [L1], pass to the opposite abelian category. Reversing arrows turns the given injective resolutions from [L2] into projective resolutions there, and becomes a morphism in the opposite direction. Apply [L3] in the opposite category to obtain the required comparison map.
Translating that chain map back to the original category reverses arrows again and yields a cochain map extending .