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Author Archives: topologyandgrouptheory
The Griffiths twin cone and the harmonic archipelago have isomorphic fundamental group (Part 3)
We saw in the previous post that the problem of producing our isomorphism is solved provided we can produce a sufficiently large coherent collection of coi triples. But how is this to be accomplished? For example, given a (perhaps quite … Continue reading
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The Griffiths twin cone and the harmonic archipelago have isomorphic fundamental group (Part 2)
This is Part 2 of a guest post by Sam Corson, who is a Heibronn Fellow at the University of Bristol. It will be helpful to read Part 1 first. We will furthermore overload the notation used for word concatenation … Continue reading
The Griffiths twin cone and the harmonic archipelago have isomorphic fundamental group (Part 1)
This is a guest post by Sam Corson, who is a Heibronn Fellow at the University of Bristol. This first post will provide background on the infinite word combinatorics which are used in the description of the fundamental group of … Continue reading