Timeline for Characteristic zero and characteristic $p$ in algebraic geometry
Current License: CC BY-SA 3.0
3 events
| when toggle format | what | by | license | comment | |
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| Sep 11, 2012 at 12:24 | comment | added | Qing Liu | In fact, in positive characteristic, any irreducible affine variety of positive dimension has non-trivial étale cover. See mathoverflow.net/questions/16047 | |
| Sep 11, 2012 at 8:05 | comment | added | Qing Liu | In the same spirit: Kedlaya proved in 2004 that over any field $k$ of positive characteristic, any geometrically reduced purely $n$-dimensional projective variety is a finite cover of $\mathbb P^n_k$, étale away from a hyperplane. This is false in characteristic $0$ because the affine space is simply connected. | |
| Sep 10, 2012 at 22:55 | history | answered | Jason Starr | CC BY-SA 3.0 |