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Category Archives: harmonic archipelago
The Uncountability of the Harmonic Archipelago Group
In a previous post, we discussed the fundamental group of the harmonic archipelago in some detail. One item that I skipped earlier is the fact that this group is uncountable. In this post, we’ll see why is uncountable. We’ll use … Continue reading
The Harmonic Archipelago Group is not Free
In recent posts, I’ve been writing about the behavior of fundamental groups of the most fundamental “wild” spaces. We did a decent amount of work in a two-part post to convince ourselves that the fundamental group of the earring space … Continue reading
The Harmonic Archipelago
Another fascinating space that receives a lot of attention is the so-called harmonic archipelago which is the following subspace of . You can describe the construction like this: Start by drawing the usual earring space onto a solid disk in … Continue reading
Wild Topology 