Timeline for A DVR algebra with weird automorphisms
Current License: CC BY-SA 4.0
4 events
| when toggle format | what | by | license | comment | |
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| Jul 13, 2019 at 16:06 | comment | added | David Lampert | For any field $k$ every discrete valuation on $k((x))$ is trivial on $k$, as noted in the comment by YCor after the answer of Will Sawin in the link above, and thus every automorphism of $k((x))$ preserves $k[[x]]$. | |
| Jul 13, 2019 at 6:36 | comment | added | Laurent Moret-Bailly | This argument seems to prove only that every automorphism preserving $k$ preserves $k[[x]]$. Fortunately, $k$ is assumed algebraically closed, so every discrete valuation on $k((x))$ is trivial on $k$. | |
| Jul 12, 2019 at 19:57 | history | edited | David E Speyer | CC BY-SA 4.0 |
added 9 characters in body
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| Jul 12, 2019 at 19:36 | history | answered | David E Speyer | CC BY-SA 4.0 |