Zulip Chat Archive

Stream: Is there code for X?

Topic: Residue field of HeightOneSpectrum


Kevin Buzzard (Jul 30 2025 at 08:59):

If AA is a Dedekind domain (it's 𝓞 F for F a number field in my application) and if v : HeightOneSpectrum A then what's the way to talk about the residue field of v? Is it just 𝓞 F ⧸ v.asIdeal ? This doesn't seem to have a Field instance...

Edward van de Meent (Jul 30 2025 at 11:38):

the issue seems to be that Ideal.Quotient.field is not an instance (see docstring for why)

Yakov Pechersky (Jul 30 2025 at 12:05):

We have docs#Ideal.ResidueField

Yakov Pechersky (Jul 30 2025 at 12:06):

But that's for the localization, which won't work as well here. You might need to construct your equivalent of docs#IsLocalRing.ResidueField


Last updated: Dec 20 2025 at 21:32 UTC