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.
Representable Hom functors on a triangulated category are homological or cohomological
Statement
For each , is homological and is cohomological, both valued in abelian groups.
Facts & Assumptions
Given: A distinguished triangle and an object .
Proof
TR1 and TR3 first give . If satisfies , compare the appropriately rotated identity triangle of with the given triangle; TR3 supplies with . Rotating the given triangle gives the same factorisation at every translated term.
Thus is homological. The dual rotated-identity-triangle argument gives exactness for with the arrows reversed, so it is cohomological.
Depends on
Used by
Dependency tree · two levels
18 results within two dependency steps of this one, each drawn at its shortest distance from it. An arrow runs from a result to what uses it, so the chart reads left to right and ends at this result, which carries a heavier outline. Every node is a link to that result. Click elsewhere on the chart to enlarge it.
Sources
- The Stacks Project, Lemma 13.4.2 (standard reference, not scraped)