Timeline for Is the direct limit of Weil restriction of an elliptic curve a scheme?
Current License: CC BY-SA 2.5
11 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Nov 4, 2010 at 6:17 | vote | accept | Dror Speiser | ||
| Nov 4, 2010 at 3:21 | answer | added | BCnrd | timeline score: 7 | |
| Nov 3, 2010 at 22:22 | comment | added | Dror Speiser | Or, in other words, I know close to nothing on group schemes. Will pick it up at some point. | |
| Nov 3, 2010 at 22:09 | comment | added | Dror Speiser | But they are finite! | |
| Nov 3, 2010 at 21:54 | comment | added | Kevin Buzzard | Finite groups are projective and complete :-/ | |
| Nov 3, 2010 at 21:40 | comment | added | Dror Speiser | The question is wether the limit exists in the category of schemes. While similar to roots of unity, it also feels that it might behave better because of projectiveness and completeness and stuff. | |
| Nov 3, 2010 at 21:28 | comment | added | Kevin Buzzard | My gut feeling is that there will no limit in the category of schemes (but I can't prove it offhand; sounds accessible though). It feels a bit analogous to the direct limit of $\mu_{p^n}$, which I don't think exists either. The problem is that projective limits in the category of rings correspond to direct limits in the category of affine schemes but not, if I remember correctly, in the category of schemes. | |
| Nov 3, 2010 at 21:08 | comment | added | Dror Speiser | It's crazy stuff! What happens when we take the limit in the category of schemes? | |
| Nov 3, 2010 at 20:52 | comment | added | Kevin Buzzard | [and then of course the next question, if you don't say "schemes" as an answer to the previous question, is "what do you mean by the direct limit 'being' a scheme?"] | |
| Nov 3, 2010 at 20:42 | comment | added | Kevin Buzzard | This question does not quite make sense to me. You say "the direct limit"---in which category are you taking this direct limit? | |
| Nov 3, 2010 at 20:33 | history | asked | Dror Speiser | CC BY-SA 2.5 |