Definition:Local Ring/Commutative
< Definition:Local Ring(Redirected from Definition:Commutative Local Ring)
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Definition
Let $A$ be a commutative ring with unity.
Definition 1
The ring $A$ is local if and only if it has a unique maximal ideal.
Definition 2
The ring $A$ is local if and only if it is nontrivial and the sum of any two non-units is a non-unit.
Definition 3
Let $M \subseteq A$ be the subset of the non-units of $A$.
The ring $A$ is local if and only if $M$ is a proper ideal of $A$.
Also denoted as
One also writes $\struct {A, \mathfrak m}$ for a commutative local ring $A$ with maximal ideal $\mathfrak m$.
Also see
- Results about local rings can be found here.