--- date: 2022-01-15 21:49 modification date: Sunday 23rd January 2022 18:56:17 title: DVR aliases: ["DVR", "DVRs", "discrete valuation"] --- Last modified date: <%+ tp.file.last_modified_date() %> --- - Tags: - #NT/algebraic #CA - Refs: - #todo/add-references - Links: - [valuation](Unsorted/Valuations.md) - [dominant](Unsorted/dominant%20morphism.md) --- # DVR - Slogan: a local PID that is not a field. The Noether regular local rings of dimension 1 are exactly the DVRs. - Vague analogy: DVRs are supposed to look like $\DD \subseteq \CC$? - Some nice properties of DVRs: - [Noetherian](Noetherian) - [PID](PID) - [local](Unsorted/localization%20of%20rings.md) - [Krull dimension](Unsorted/Krull%20dimension.md) one - [regular](Unsorted/regular%20ring.md) - [integrally closed](integrally%20closed) ![](attachments/Pasted%20image%2020220123185627.png) ![](attachments/Pasted%20image%2020220123185915.png) - Scheme-theoretic properties: for $R\in\DVR$, $\spec R = \ts{ (0), \mfm}$ consists of a [generic point](generic%20point) and the [special point](special%20point). - The ring of integers of a nonarchimedean local field is a complete DVR with finite residue field ![](attachments/Pasted%20image%2020220914181713.png) ![](attachments/Pasted%20image%2020220914181903.png) ![](attachments/Pasted%20image%2020221111232225.png)