Module

RingCover.lean

Nyll.SchemeTheory.FiniteEtale.RingCover
3 declarations indexed from sourceView source ↗

Field Arithmetic, Definition 7.1.3: ring covers

The book's condition S = R[z] is recorded by the existence of a power basis. The Galois condition is stated for the induced extension of fraction fields.

Imports4
  • Mathlib.FieldTheory.Galois.Basic
  • Mathlib.RingTheory.Discriminant
  • Mathlib.RingTheory.Localization.FractionRing
  • Mathlib.RingTheory.PowerBasis
Imported by1

Declarations

FieldArithmetic.Chapter07.IsRingCover

The algebraic part of the ring-cover condition in Fried--Jarden, Definition 7.1.3. The ambient hypotheses that R and S are integrally closed domains are supplied where this predicate is used.

Source context 7 commands

Surrounding namespaces, section variables, and local commands at this declaration.

noncomputable section
namespace FieldArithmetic
namespace Chapter07
universe u v
variable (R : Type u) (S : Type v)
variable [CommRing R] [CommRing S]
variable [Algebra R S]
def IsRingCover : Prop
FieldArithmetic.Chapter07.FractionExtensionIsGalois

The extension of fraction fields induced by R → S is Galois.

Source context 7 commands

Surrounding namespaces, section variables, and local commands at this declaration.

noncomputable section
namespace FieldArithmetic
namespace Chapter07
universe u v
variable (R : Type u) (S : Type v)
variable [CommRing R] [CommRing S]
variable [Algebra R S]
def FractionExtensionIsGalois [IsDomain S] [FaithfulSMul R S] : Prop
FieldArithmetic.Chapter07.IsGaloisRingCover

The algebraic part of the Galois ring-cover condition in Definition 7.1.3.

Source context 7 commands

Surrounding namespaces, section variables, and local commands at this declaration.

noncomputable section
namespace FieldArithmetic
namespace Chapter07
universe u v
variable (R : Type u) (S : Type v)
variable [CommRing R] [CommRing S]
variable [Algebra R S]
def IsGaloisRingCover [IsDomain S] [FaithfulSMul R S] : Prop