Timeline for Extension of covering map
Current License: CC BY-SA 3.0
4 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Oct 8, 2012 at 0:44 | comment | added | Igor Rivin | Your point is well-taken. The surfaces should have positive genus, otherwise the problem is either very easy but with a different answer (like your example) or extremely hard (like a sphere with three holes). | |
| Oct 8, 2012 at 0:30 | comment | added | Alexandre Eremenko | I don't understand something about the result on surfaces you cite. Let M=N=unit disc. The covering of the boundary circle $z\mapsto z^n$ evidently extends to a covering of the discs only when $n=\pm 1$. What does this have to do with the sign of the permutation (which is a cycle in our case)? | |
| Oct 8, 2012 at 0:23 | answer | added | Ian Agol | timeline score: 6 | |
| Oct 7, 2012 at 23:58 | history | asked | Igor Rivin | CC BY-SA 3.0 |