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.
normal domain implies r one
Statement
Every commutative Noetherian integrally closed domain satisfies .
Facts & Assumptions
Given: The objects and hypotheses in the statement.
serre r k and s k conditions: For a commutative Noetherian ring and an integer , condition means that is regular whenever . Condition means that for every prime . A finite module satisfies if for every prime in its support. Outside the support the condition is vacuous, consistent with depth of the zero module being and the empty support having no nonnegative dimension. Thus the zero module satisfies all conditions, and the zero ring satisfies both families vacuously.
Height-one localizations of normal Noetherian domains are DVRs: Let be a Noetherian integrally closed domain, and let be a prime ideal of height . Then the localisation is a discrete valuation ring.
embedding dimension and regular local ring: A nonzero Noetherian local ring is regular when .
Proof
A height-one localization is a DVR by [F2], so it has dimension one and a nonzero principal maximal ideal . Since is a domain and is a nonunit, : otherwise cancellation would make a unit. Thus is a one-dimensional vector space over , generated by the nonzero class of . Its embedding dimension equals its dimension, so is regular.
The only height-zero prime of a domain is ; its localization is the fraction field, which is regular. These two cases give the definition of , including a field, which has no height-one primes.
Depends on
Used by
- serre normality criterion two directions Corollary
- A normal-surface modification is an isomorphism in codimension one Lemma
- Normalized point blowups dominate local normal surface modifications Lemma
- Positive conormal degree for a fibre divisor on a normal surface Lemma
- Surface resolution globalizes from complete local point resolutions Lemma
Dependency tree · two levels
14 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
- 10.157.4 forward implication (standard reference, not scraped)