Elementary abelian group: Difference between revisions
|  (Started the page) |  (Examples) | ||
| (5 intermediate revisions by 2 users not shown) | |||
| Line 5: | Line 5: | ||
| ===Symbol-free definition=== | ===Symbol-free definition=== | ||
| An '''elementary  | An '''elementary abelian group''' is a group that satisfies the following equivalent conditions: | ||
| * It is an  | * It is an abelian [[characteristically simple group]] | ||
| * It is a direct product of isomorphic subgroups, each being cyclic of prime order | * It is a [[restricted direct product]] of isomorphic subgroups, each being cyclic of prime order | ||
| * It is the additive group of a vector space over a prime field | * It is the additive group of a vector space over a prime field | ||
| * It is abelian and all elements other than the identity have the same order | |||
| ==Examples== | |||
| ===Finite groups=== | |||
| The finite elementary abelian groups are precisely those of the form <math>(\mathbb{Z}_p)^n</math> for some <math>p, n \in \mathbb{Z}</math>, <math>p</math> prime. | |||
| * In particular, all cyclic groups of prime order are elementary abelian groups. [[Equivalence of definitions of group of prime order|Since there is only one group up to isomorphism of prime order, which is cyclic]], all groups of prime order are elementary abelian groups. | |||
| * [[Elementary abelian group:E4]], the direct product <math>\mathbb{Z}_2 \times \mathbb{Z}_2</math>, also known as the Klein four-group. | |||
| * [[Elementary abelian group:E8]], the direct product <math>\mathbb{Z}_2 \times \mathbb{Z}_2 \times \mathbb{Z}_2</math> | |||
| * [[Elementary abelian group:E9]], the direct product <math>\mathbb{Z}_3 \times \mathbb{Z}_3</math> | |||
| * [[Elementary abelian group:E16]], the direct product <math>\mathbb{Z}_2 \times \mathbb{Z}_2 \times \mathbb{Z}_2 \times \mathbb{Z}_2</math> | |||
| * [[Elementary abelian group:E25]], the direct product <math>\mathbb{Z}_5 \times \mathbb{Z}_5</math> | |||
| ===Infinite groups=== | |||
| {{fillin}} | |||
| ==Relation with other properties== | ==Relation with other properties== | ||
| Line 22: | Line 41: | ||
| * [[Abelian group]] | * [[Abelian group]] | ||
| * [[Characteristically simple group]] | * [[Characteristically simple group]] | ||
| ==Facts== | |||
| ===Minimal normal subgroups=== | |||
| Any [[minimal normal subgroup]] in a [[solvable group]] must be elementary Abelian. This follows by combining the fact that it must be [[Abelian group|Abelian]] with the fact that in any group, a minimal normal subgroup is always [[characteristically simple group|characteristically simple]]. | |||
Latest revision as of 10:36, 22 October 2023
This article defines a group property: a property that can be evaluated to true/false for any given group, invariant under isomorphism
View a complete list of group properties
VIEW RELATED: Group property implications | Group property non-implications |Group metaproperty satisfactions | Group metaproperty dissatisfactions | Group property satisfactions | Group property dissatisfactions
Definition
Symbol-free definition
An elementary abelian group is a group that satisfies the following equivalent conditions:
- It is an abelian characteristically simple group
- It is a restricted direct product of isomorphic subgroups, each being cyclic of prime order
- It is the additive group of a vector space over a prime field
- It is abelian and all elements other than the identity have the same order
Examples
Finite groups
The finite elementary abelian groups are precisely those of the form for some , prime.
- In particular, all cyclic groups of prime order are elementary abelian groups. Since there is only one group up to isomorphism of prime order, which is cyclic, all groups of prime order are elementary abelian groups.
- Elementary abelian group:E4, the direct product , also known as the Klein four-group.
- Elementary abelian group:E8, the direct product
- Elementary abelian group:E9, the direct product
- Elementary abelian group:E16, the direct product
- Elementary abelian group:E25, the direct product
Infinite groups
PLACEHOLDER FOR INFORMATION TO BE FILLED IN: [SHOW MORE]
Relation with other properties
Stronger properties
- Cyclic group of prime order viz. simple Abelian group
Weaker properties
Facts
Minimal normal subgroups
Any minimal normal subgroup in a solvable group must be elementary Abelian. This follows by combining the fact that it must be Abelian with the fact that in any group, a minimal normal subgroup is always characteristically simple.