Timeline for Quotient variety and subgroups
Current License: CC BY-SA 4.0
9 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Oct 6, 2021 at 14:25 | vote | accept | Tommaso Scognamiglio | ||
| Oct 6, 2021 at 14:20 | comment | added | Damian Rössler | The issue is (I believe this is what afh's answer illustrates) is that the scheme-theoretic intersection of a $G$-orbit in $X$ with $Y$ might be non reduced. | |
| Oct 6, 2021 at 12:14 | answer | added | afh | timeline score: 4 | |
| Oct 4, 2021 at 20:50 | history | edited | LSpice | CC BY-SA 4.0 |
Typos
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| Oct 4, 2021 at 20:42 | comment | added | Tommaso Scognamiglio | Unfortunately I don't have any hypothesis on normality or smoothness in the case I'm interested :( | |
| Oct 4, 2021 at 20:41 | history | edited | Tommaso Scognamiglio | CC BY-SA 4.0 |
added 55 characters in body
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| Oct 4, 2021 at 18:00 | comment | added | Damian Rössler | See also mathoverflow.net/questions/264204/… | |
| Oct 4, 2021 at 17:54 | comment | added | Damian Rössler | Suppose that $X$ is normal. Then $X/G$ is also normal. Also, $f$ is quasi-finite and birational (because the extension of function fields is separable, and hence of degree one, since we are in char. $0$). Hence by Zariski's main theorem $f$ is an open immersion and hence an isomorphism. | |
| Oct 4, 2021 at 16:53 | history | asked | Tommaso Scognamiglio | CC BY-SA 4.0 |