Cohen–Macaulay ring
E790527
A Cohen–Macaulay ring is a commutative Noetherian ring whose depth equals its Krull dimension, giving it especially well-behaved homological and geometric properties.
Observed surface forms (1)
| Surface form | Occurrences |
|---|---|
| Cohen–Macaulay rings | 1 |
Statements (51)
| Predicate | Object |
|---|---|
| instanceOf |
Noetherian ring
ⓘ
algebraic structure ⓘ commutative ring ⓘ mathematical object ⓘ |
| characterizedBy |
depth equals dimension at all localizations at prime ideals
ⓘ
existence of a full-length regular sequence in every maximal ideal ⓘ |
| definedBy | depth(R) = dim(R) ⓘ |
| equivalentCondition |
depth of localizations at all prime ideals equals their Krull dimension
ⓘ
every system of parameters is an R-regular sequence ⓘ |
| fieldOfStudy |
algebraic geometry
ⓘ
commutative algebra ⓘ |
| generalizes | regular local ring ⓘ |
| hasCondition |
all systems of parameters are regular sequences
ⓘ
depth of every maximal ideal equals Krull dimension ⓘ |
| hasExample |
complete intersection ring
ⓘ
coordinate ring of a nonsingular affine variety over a field ⓘ regular local ring ⓘ standard graded k-algebra that is Cohen–Macaulay ⓘ |
| hasGeometricInterpretation | coordinate ring of a Cohen–Macaulay scheme ⓘ |
| hasHomologicalProperty |
finite projective dimension for canonical modules when they exist
ⓘ
vanishing of certain local cohomology modules below top dimension ⓘ |
| hasInvariant |
Krull dimension
NERFINISHED
ⓘ
depth ⓘ |
| hasModule | maximal Cohen–Macaulay module ⓘ |
| hasOriginIn | study of Hilbert functions and syzygies ⓘ |
| hasProperty |
Noetherian
ⓘ
depth equals Krull dimension ⓘ well-behaved geometric properties ⓘ well-behaved homological properties ⓘ |
| hasSpecialModule | canonical module ⓘ |
| implies |
equidimensional localizations at maximal ideals
ⓘ
unmixed ring ⓘ |
| isLocalVersion | Cohen–Macaulay local ring ⓘ |
| isStableUnder |
completion at an ideal
ⓘ
finite integral extension under suitable hypotheses ⓘ localization ⓘ polynomial extension over a Cohen–Macaulay base ⓘ |
| namedAfter |
Francis Sowerby Macaulay
NERFINISHED
ⓘ
Irvin Cohen NERFINISHED ⓘ |
| relatedConcept |
Gorenstein ring
NERFINISHED
ⓘ
Krull dimension NERFINISHED ⓘ Serre’s conditions (S_n) ⓘ complete intersection ring ⓘ depth of a module ⓘ local cohomology ⓘ regular sequence ⓘ |
| satisfies | Serre’s condition (S_dim R) ⓘ |
| usedIn |
intersection theory
ⓘ
local algebra ⓘ singularity theory ⓘ theory of Hilbert functions ⓘ |
Referenced by (2)
Full triples — surface form annotated when it differs from this entity's canonical label.
subject surface form:
Introduction to Commutative Algebra
this entity surface form:
Cohen–Macaulay rings