Conjugate-commensurable subgroup: Difference between revisions

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| [[Weaker than::nearly normal subgroup]] || [[subgroup of finite index]] in its [[normal closure]] || || ||  
| [[Weaker than::nearly normal subgroup]] || [[subgroup of finite index]] in its [[normal closure]] || || ||  
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| [[Weaker than::almost normal subgroup]] || its [[normal core]] is a [[subgroup of finite index]] in it || || ||
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| [[Weaker than::isomorph-commensurable subgroup]] || commensurable with every isomorphic subgroup || || ||  
| [[Weaker than::isomorph-commensurable subgroup]] || commensurable with every isomorphic subgroup || || ||  

Latest revision as of 15:04, 9 March 2020

BEWARE! This term is nonstandard and is being used locally within the wiki. [SHOW MORE]

This article defines a subgroup property: a property that can be evaluated to true/false given a group and a subgroup thereof, invariant under subgroup equivalence. View a complete list of subgroup properties[SHOW MORE]

This is a variation of normal subgroup|Find other variations of normal subgroup | Read a survey article on varying normal subgroup

Definition

Symbol-free definition

A subgroup of a group is termed conjugate-commensurable if it is commensurable with each of its conjugate subgroups. Equivalently, its commensurator in the whole group is the whole group.

Definition with symbols

A subgroup of a group is termed a conjugate-commensurable subgroup if, for any , has finite index in both and .

Relation with other properties

Stronger properties

Property Meaning Proof of implication Proof of strictness (reverse implication failure) Intermediate notions
normal subgroup |FULL LIST, MORE INFO
subgroup of finite group
finite subgroup
subgroup of finite index |FULL LIST, MORE INFO
nearly normal subgroup subgroup of finite index in its normal closure
isomorph-commensurable subgroup commensurable with every isomorphic subgroup
automorph-commensurable subgroup commensurable with every automorphic subgroup