Timeline for When does 'Zariski tangent space derivative' vanishes everywhere imply that a section is constant?
Current License: CC BY-SA 3.0
9 events
when toggle format | what | by | license | comment | |
---|---|---|---|---|---|
Dec 10, 2015 at 7:39 | answer | added | Qiaochu Yuan | timeline score: 4 | |
Dec 9, 2015 at 22:03 | comment | added | James E Hanson | There was no $K$ in the question when მამუკა ჯიბლაძე responded. | |
Dec 9, 2015 at 21:46 | comment | added | Julian Rosen | @მამუკაჯიბლაძე There is a canonical choice of splitting map $R/m\to R/m^2$, which identifies $R/m$ with $K$ then includes into $R/m^2$ by the structure map (the map making $R/m^2$ into a $K$-algebra). | |
Dec 9, 2015 at 21:12 | history | edited | James E Hanson | CC BY-SA 3.0 |
Restricted to K-algebra case to make the problem well-posed.
|
Dec 9, 2015 at 21:07 | comment | added | James E Hanson | Yes that's true. I'll edit the question to make it more specific. | |
Dec 9, 2015 at 20:36 | history | edited | Leo Alonso |
edited tags
|
|
Dec 9, 2015 at 20:33 | comment | added | მამუკა ჯიბლაძე | Does not the answer depend on the choice of an isomorphism $R/m^2\cong R/m\oplus m/m^2$? I don't see any canonical map which one might require to be an isomorphism. There are maps $m/m^2\to R/m^2\to R/m$, one may require this to be a split short exact sequence, but a choice of the splitting still has to be made, and I think the answer will depend on it. | |
Dec 9, 2015 at 20:02 | review | First posts | |||
Dec 9, 2015 at 20:03 | |||||
Dec 9, 2015 at 19:58 | history | asked | James E Hanson | CC BY-SA 3.0 |