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Tweets
Tweets by jtbrazas-
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Tag Archives: van-Kampen theorem
The “tau topology” on the fundamental group
In the multipart series on topologies on fundamental groups, we’ve discussed the fundamental group with the quotient topology: . This is defined as having the quotient topology with respect to the map , that identifies homotopic loops. Here, is the … Continue reading
Posted in Category Theory, coreflection functor, Fundamental group, Quasitopological groups, quasitopological groups, quotient topology, reflection functor, topological fundamental group, Topological groups, Uncategorized
Tagged free topological group, fundamental group, quasitopological group, reflection functor, topological group, van-Kampen theorem, wedge of circles
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The Griffiths Twin Cone
This post is about an important wild space which, in many ways, is similar to the harmonic archipelago space that I posted about a few weeks ago. The Griffiths twin cone (or Griffiths space) was first studied by H.B. Griffiths in the 1950’s … Continue reading
Wild Topology 