17
votes
1answer
666 views
Can the Alexander horned sphere arise as a cell boundary in a finite CW-sphere?
Recently, I've been wondering to what extent certain types of pathologies can arise in finite CW complexes -- notice that I do not want to assume that I'm in the PL category or tha …
7
votes
6answers
2k views
Fundamental group of the line with the double origin.
In the simplest cases, the fundamental group serves as a measure of the number of 2-dimensional "holes" in a space. It is interesting to know whether they capture the following typ …
