Timeline for Can a non-surjective polynomial map from an infinite field to itself miss only finitely many points?
Current License: CC BY-SA 2.5
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| Sep 12, 2023 at 16:19 | review | Low quality posts | |||
| Sep 12, 2023 at 18:41 | |||||
| Nov 30, 2009 at 7:23 | comment | added | Kevin Buzzard | By "A^1 over Q" I meant Spec(Q[x]). If I had written A^1(Q) I would have meant Q. Careful though, I don't think I wrote A^1(Q). For me "X over Q" and "X(Q)" mean different things. One is the assertion that the equations defining X have coefficients in Q. The other is the set of their solutions. | |
| Nov 30, 2009 at 3:36 | comment | added | Qiaochu Yuan | buzzard, by A^1(Q) do you mean MaxSpec Q[x]? | |
| Nov 28, 2009 at 14:57 | comment | added | Kevin Buzzard | This reminds me of the first time I worked out what the topological space underlying affine 1-space over Q was (and what the top space map from A^1 over C to A^1 over Q (induced by the obvious inclusion of rings) looked like). I was horrified! | |
| Nov 27, 2009 at 21:45 | comment | added | Kevin Buzzard | Yes. The question is arithmetic, not geometric. Squaring is a degree 2 map from affine 1-space onto itself. But that doesn't mean that every element of a random field is a square | |
| Nov 27, 2009 at 21:39 | history | undeleted | AFK | ||
| Nov 27, 2009 at 21:39 | history | edited | AFK | CC BY-SA 2.5 |
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| Nov 27, 2009 at 21:25 | history | deleted | AFK | ||
| Nov 27, 2009 at 21:20 | history | answered | AFK | CC BY-SA 2.5 |