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.
fields as regular local rings
Example
Every field is regular local with dimension and embedding dimension zero. Conversely every zero-dimensional regular local ring is a field. Its regular system is empty and its residue field has a free resolution concentrated in degree zero.
Facts & Assumptions
Given: The objects and hypotheses in the example. We work with the Axiom of Choice; cited dependent-choice and resolution-existence hypotheses are retained.
embedding dimension and regular local ring: For a nonzero commutative Noetherian local ring , define . The ring is regular local when . The cotangent space is intrinsic, and is finite-dimensional because is finitely generated.
Assuming the Axiom of Choice, Nakayama's lemma: Assume the Axiom of Choice. Let be a commutative ring, let satisfy , and let be a finitely generated left -module. If , then .
Verification
A field has the single prime and maximal ideal , so its dimension and cotangent dimension are both zero. It is regular by definition. The empty tuple generates its maximal ideal and is its length-zero augmented resolution.
For a zero-dimensional regular local ring, . Nakayama applied to the finite ideal gives . Every element outside the maximal ideal is a unit, so the ring is a field.
Depends on
Used by
Nothing in the library uses this result yet.
Dependency tree · two levels
8 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
- Example 12.6, p.115 (standard reference, not scraped)