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Category Archives: Free groups
Shape injectivity of the earring space (Part II)
This is the sequel to Shape injectivity of the earring space (Part I) We’re on our way to proving the canonical homomorphism from the earring group to the inverse limit of free groups is injective. Part I was mostly dedicated … Continue reading
Shape injectivity of the earring space (Part I)
One of my posts where I did some substantial handwaving is my original post on the fundamental group of the earring space. I wrote about how to understand and work with this group, but I never gave a proof of … Continue reading
Posted in Free groups, Fundamental group, Hawaiian earring, Inverse Limit, Tree
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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