Timeline for Degrees of self-maps of aspherical manifolds
Current License: CC BY-SA 2.5
7 events
| when toggle format | what | by | license | comment | |
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| Oct 16, 2010 at 10:28 | comment | added | X.M. Du | @Rpotrie: Due to A. Edmonds, every surface map can be homotopically decomposited to pinchings and branch coverings. And pinchings do not change the mapping degree. So the Hurwitz formula of branch coverings is sufficient to show the degree cannot be larger than 1. | |
| Oct 15, 2010 at 3:42 | answer | added | Ian Agol | timeline score: 9 | |
| Oct 14, 2010 at 16:44 | comment | added | rpotrie | en.wikipedia.org/wiki/Riemann–Hurwitz_formula should be useful, however, as in Richard Kent's answer, it must be showed that a map of degree bigger than $1$ is homotopic to a covering map. | |
| Oct 14, 2010 at 16:36 | history | edited | Dmitri Panov | CC BY-SA 2.5 |
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| Oct 14, 2010 at 16:32 | answer | added | Andreas Thom | timeline score: 10 | |
| Oct 14, 2010 at 16:32 | answer | added | Autumn Kent | timeline score: 7 | |
| Oct 14, 2010 at 16:21 | history | asked | Johannes Ebert | CC BY-SA 2.5 |