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Tweets by jtbrazas-

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# Category Archives: Griffiths twin cone

## 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

## Homotopically Hausdorff Spaces (Part I)

In previous posts, I wrote about the harmonic archipelago (see also here and here): as well as the Griffiths Twin Cone . One special feature of these 2-dimensional spaces is that any loop either of these spaces can be deformed to lie … Continue reading