DefinitionDefinition: Literature-sourcedProof: Not applicableaudited 2026-08-11
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.
A free group action has no nonidentity element fixing a point
Definition
A left action of a group on a set (Left group actions, transitive actions, and faithful actions) is free when
for every and . Equivalently, no nonidentity element of fixes any point of .