Stewart's theorem: Difference between revisions

From formulasearchengine
Jump to navigation Jump to search
en>Circlesareround
m →‎Proof: italic variables
→‎Proof: i removed the faulty :
Line 1: Line 1:
In [[mathematics]], in the realm of [[Abelian group|abelian]] [[group theory]], a [[Group (mathematics)|group]] is said to be '''algebraically compact''' if it is a [[direct summand]] of every abelian group containing it as a [[pure subgroup]].
I would like to introduce myself to you, I am Andrew and my spouse doesn't like it at all. My spouse and I live in Kentucky. My working day job is a journey agent. To climb is something I truly enjoy performing.<br><br>Feel free to surf to my web-site - [http://www.skullrocker.com/blogs/post/10991 online psychic chat]
 
Equivalent characterizations of algebraic compactness:
* The group is complete in the <math>\mathbb{Z}</math> adic topology.
* The group is ''pure injective'', that is, injective with respect to exact sequences where the embedding is as a pure subgroup.
 
Relations with other properties:
* A [[torsion-free group]] is [[cotorsion group|cotorsion]] if and only if it is algebraically compact.
* Every [[injective group]] is algebraically compact.
* [[Ulm factor]]s of cotorsion groups are algebraically compact.
==External links==
* [http://www.springerlink.com/index/W3W06361813J347X.pdf On endomorphism rings of Abelian groups]
[[Category:Abelian group theory]]
[[Category:Properties of groups]]

Revision as of 06:34, 9 February 2014

I would like to introduce myself to you, I am Andrew and my spouse doesn't like it at all. My spouse and I live in Kentucky. My working day job is a journey agent. To climb is something I truly enjoy performing.

Feel free to surf to my web-site - online psychic chat