Multiplicative Euclidean norm: Difference between revisions

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{{Euclidean norm property}}
{{curing-norm property conjunction|multiplicative norm|Euclidean norm}}


==Definition==
==Definition==


A [[Euclidean norm]] on a [[commutative unital ring]] is termed '''multiplicative''' if the norm of the product of two elements is the product of their norms. Multiplicative Euclidean norms that are nonzero on at least some nonzero element, must take the value <math>1</math> at all units.
A '''multiplicative Euclidean norm''' is a function from a [[commutative unital ring]] to the nonnegative integers that satisfies the following two conditions:
 
* It is a [[multiplicative norm]]: The norm of a nonzero product of two elements equals the product of their norms.
* It is a [[Euclidean norm]].


==Examples==
==Examples==
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The absolute value on the [[ring of rational integers]] (<math>\mathbb{Z}</math>) is a multiplicative Euclidean norm. So is the square of the complex modulus, on the [[ring of Gaussian integers]].
The absolute value on the [[ring of rational integers]] (<math>\mathbb{Z}</math>) is a multiplicative Euclidean norm. So is the square of the complex modulus, on the [[ring of Gaussian integers]].


In general, the [[norm function on a ring of integers]] is multiplicative, and thus, if it is also a Euclidean norm, it is a multiplicative Euclidean norm.
In general, the [[algebraic norm in a number field]] is multiplicative, and so is its restriction to the [[ring of integers in a number field|ring of integers]].
 
==Relation with other properties==
 
===Weaker properties===
 
* [[Stronger than::Multiplicative Dedekind-Hasse norm]]
* [[Stronger than::Multiplicative norm]]
* [[Stronger than::Euclidean norm]]

Latest revision as of 19:46, 23 January 2009

This article defines a property of a norm on a commutative unital ring obtained as the conjunction of two properties: multiplicative norm and Euclidean norm.
View a complete list of such conjunctions | View a complete list of properties of norms in commutative unital rings

Definition

A multiplicative Euclidean norm is a function from a commutative unital ring to the nonnegative integers that satisfies the following two conditions:

Examples

The absolute value on the ring of rational integers (Z) is a multiplicative Euclidean norm. So is the square of the complex modulus, on the ring of Gaussian integers.

In general, the algebraic norm in a number field is multiplicative, and so is its restriction to the ring of integers.

Relation with other properties

Weaker properties