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.
Corestriction after restriction multiplies by the index
Statement
If has finite index, then on for all .
Proof
Given: A finite-index subgroup and a left -module .
In degree zero, if , restriction regards as -fixed and the norm sends it to . Thus and multiplication by have the same degree-zero component.
Both are morphisms from the universal cohomological delta functor to itself. By A morphism between universal delta functors is determined in degree zero, equality in degree zero forces equality in every degree. Hence the composite is multiplication by on for all .
Depends on
Used by
Dependency tree · two levels
12 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
- Weibel, Lemma 6.7.17 (standard reference, not scraped)