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Category Archives: Group homomorphisms
Homotopically Hausdorff Spaces (Part II)
In my post homotopically Hausdorff spaces (Part I), I wrote about the property which describes the existence of loops that can be deformed into arbitrarily small neighborhoods but which are not actually nullhomotopic, i.e. can’t be deformed all the way back … Continue reading
The BaerSpecker Group
One of the infinite abelian groups that is important to infinite abelian group theory and which has shown up naturally in previous posts on infinitary fundamental groups is the BaerSpecker group, often just called the Specker group. This post isn’t … Continue reading
Homomorphisms from the earring group to finite groups
One of the the surprising things about the earring group (the fundamental group of the earring space ) is that the group of homomorphisms to the additive group of integers is countable (see this post for details) even though is … Continue reading
Posted in earring group, earring space, Finite groups, Fundamental group, Group homomorphisms, Ultrafilter
Tagged anomalous, axiom of choice, cardinality, epimorphism, filter, finite group, fundamental group, Hawaiian earring, homomorphism, integers, nonprincipal ultrafilter, StoneCech compactification, uncountable
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