Maximal ideal: Difference between revisions

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==Definition for commutative rings==
{{curing-ideal property}}
 
{{quotient is a|field}}
 
==Definition==


===Symbol-free definition===
===Symbol-free definition===
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* For any ideal <math>J</math> such that <math>M</math> &le; <math>J</math> &le; <math>R</math>, <math>J</math> is equal either to <math>M</math> or to <math>R</math>.
* For any ideal <math>J</math> such that <math>M</math> &le; <math>J</math> &le; <math>R</math>, <math>J</math> is equal either to <math>M</math> or to <math>R</math>.
* The quotient ring <math>R/M</math> is a [[field]].
* The quotient ring <math>R/M</math> is a [[field]].
==Definition for non-commutative rings==
For non-commutative rings, there are three notions:
* [[Maximal two-sided ideal]]: Maximal among [[two-sided ideal]]s
* [[Maximal left ideal]]: Maximal among [[left ideal]]s
* [[Maximal right ideal]]: Maximal among [[right ideal]]s
[[Category: Properties of ideals in commutative rings]]
[[Category: Quotient-determined properties of ideals in commutative rings]]

Revision as of 09:35, 7 August 2007

This article defines a property of an ideal in a commutative unital ring |View other properties of ideals in commutative unital rings

This property of an ideal in a ring is equivalent to the property of the quotient ring being a/an: field | View other quotient-determined properties of ideals in commutative unital rings

Definition

Symbol-free definition

An ideal in a commutative unital ring (or more generally, in any commutative ring) is termed maximal if it is proper (not the whole ring) and it satisfies the following equivalent conditions:

  • There is no ideal of the ring properly in between this ideal and the whole ring
  • The quotient of the ring by this ideal is a field
  • The natural action of on makes into a simple -module.

Definition with symbols

An ideal in a commutative ring is termed maximal if it satisfies the following equivalent conditions:

  • For any ideal such that , is equal either to or to .
  • The quotient ring is a field.