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.
Two supplied projective resolution data define naturally isomorphic left derived functors
Statement
Assume the Axiom of Dependent Choice.
Let and be supplied projective resolution data on the same domain, and let be an additive functor. For every , the additive functors and are naturally isomorphic.
Facts & Assumptions
Given: An integer .
Both constructions define additive functors (Left derived functors relative to supplied data are additive functors).
For each object, objectwise comparison of the two chosen resolutions induces an isomorphism on derived objects (Objectwise comparison of two projective resolution data induces an isomorphism on derived objects).
Those isomorphisms are natural in the object (The change-of-projective-resolution isomorphisms are natural).
Proof
By [L2], each object carries an isomorphism .
By [L3], the family from step 1.1 is natural. Together with [L1], this is exactly a natural isomorphism of additive functors .