Timeline for Fundamental group of R^2-Q^2
Current License: CC BY-SA 3.0
7 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Jun 12, 2011 at 21:29 | vote | accept | Avi Steiner | ||
| Jun 12, 2011 at 0:03 | comment | added | David Roberts♦ | Perhaps the simple question of 'what is this fundamental group?' is not a good fit for MO. But I think there is something to be learned from this example, namely, you don't really want the fundamental group in this case, but something else. This 'something else' is detailed in my answer. | |
| Jun 12, 2011 at 0:00 | answer | added | David Roberts♦ | timeline score: 21 | |
| Jun 11, 2011 at 23:49 | comment | added | Ryan Budney | What does it mean for a group to be "known"? Fundamental groups of subsets of the plane have a certain characterization (Eda 1998). But even finitely-presented groups have no classification, and this group isn't even finitely generated... | |
| Jun 11, 2011 at 23:36 | comment | added | Chris Gerig | An exercise in Hatcher's textbook asks to show that it is uncountable. | |
| Jun 11, 2011 at 23:30 | comment | added | George Lowther | This math.stackexchange question might help. math.stackexchange.com/q/16948/1321 | |
| Jun 11, 2011 at 22:44 | history | asked | Avi Steiner | CC BY-SA 3.0 |