Module

Basic.lean

Nyll.AlgebraicCurves.Differentials.Basic
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Basic

Imports2
Imported by52

Declarations

AlgebraicCurve.Place.uniformizer_alt

A chosen element of order one at the place, or zero if no such element exists.

Source context 7 commands

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

noncomputable section
open KaehlerDifferential
namespace AlgebraicCurve
variable {K F : Type*} [Field K] [Field F] [Algebra K F]
namespace Place
variable (v : Place K F)
open Classical in
def uniformizer_alt : F
AlgebraicCurve.Place.ord_uniformizer_alt
Source context 6 commands

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

noncomputable section
open KaehlerDifferential
namespace AlgebraicCurve
variable {K F : Type*} [Field K] [Field F] [Algebra K F]
namespace Place
variable (v : Place K F)
theorem ord_uniformizer_alt (h : ∃ t : F, v.ord t = 1) : v.ord v.uniformizer_alt = 1
AlgebraicCurve.Place.diffCoeff

A chosen coefficient expressing the differential as a multiple of D t, or zero if none exists.

Source context 7 commands

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

noncomputable section
open KaehlerDifferential
namespace AlgebraicCurve
variable {K F : Type*} [Field K] [Field F] [Algebra K F]
namespace Place
variable (v : Place K F)
open Classical in
def diffCoeff (t : F) (ω : Ω[F⁄K]) : F
AlgebraicCurve.Place.diffCoeff_smul_D
Source context 6 commands

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

noncomputable section
open KaehlerDifferential
namespace AlgebraicCurve
variable {K F : Type*} [Field K] [Field F] [Algebra K F]
namespace Place
variable (v : Place K F)
theorem diffCoeff_smul_D {t : F} {ω : Ω[F⁄K]} (h : ∃ g : F, ω = g • D K F t) :
    diffCoeff t ω • D K F t = ω
AlgebraicCurve.Place.diffCoeff_of_not_exists
Source context 6 commands

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

noncomputable section
open KaehlerDifferential
namespace AlgebraicCurve
variable {K F : Type*} [Field K] [Field F] [Algebra K F]
namespace Place
variable (v : Place K F)
theorem diffCoeff_of_not_exists {t : F} {ω : Ω[F⁄K]} (h : ¬ ∃ g : F, ω = g • D K F t) :
    diffCoeff t ω = 0
AlgebraicCurve.Place.ordDiff

The order of the differential coefficient with respect to the chosen uniformizer.

Source context 6 commands

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

noncomputable section
open KaehlerDifferential
namespace AlgebraicCurve
variable {K F : Type*} [Field K] [Field F] [Algebra K F]
namespace Place
variable (v : Place K F)
def ordDiff (ω : Ω[F⁄K]) : ℤ
AlgebraicCurve.Place.ordDiff_def
Source context 6 commands

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

noncomputable section
open KaehlerDifferential
namespace AlgebraicCurve
variable {K F : Type*} [Field K] [Field F] [Algebra K F]
namespace Place
variable (v : Place K F)
theorem ordDiff_def (ω : Ω[F⁄K]) : v.ordDiff ω = v.ord (diffCoeff v.uniformizer_alt ω)
AlgebraicCurve.IsRegularDiff

A differential is regular when its order is nonnegative at every place.

Source context 5 commands

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

noncomputable section
open KaehlerDifferential
namespace AlgebraicCurve
variable {K F : Type*} [Field K] [Field F] [Algebra K F]
variable (K F) in
def IsRegularDiff (ω : Ω[F⁄K]) : Prop
AlgebraicCurve.isRegularDiff_iff
Source context 5 commands

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

noncomputable section
open KaehlerDifferential
namespace AlgebraicCurve
variable {K F : Type*} [Field K] [Field F] [Algebra K F]
variable (K F) in
theorem isRegularDiff_iff (ω : Ω[F⁄K]) :
    IsRegularDiff K F ω ↔ ∀ v : Place K F, 0 ≤ v.ordDiff ω
AlgebraicCurve.regularDiffs

The submodule spanned by the differentials that are regular at every place.

Source context 6 commands

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

noncomputable section
open KaehlerDifferential
namespace AlgebraicCurve
variable {K F : Type*} [Field K] [Field F] [Algebra K F]
variable (K F) in
variable (K F) in
def regularDiffs : Submodule K Ω[F⁄K]
AlgebraicCurve.mem_regularDiffs_of_isRegularDiff
Source context 6 commands

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

noncomputable section
open KaehlerDifferential
namespace AlgebraicCurve
variable {K F : Type*} [Field K] [Field F] [Algebra K F]
variable (K F) in
variable (K F) in
theorem mem_regularDiffs_of_isRegularDiff {ω : Ω[F⁄K]} (h : IsRegularDiff K F ω) :
    ω ∈ regularDiffs K F
AlgebraicCurve.regularDiffs_eq_span
Source context 6 commands

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

noncomputable section
open KaehlerDifferential
namespace AlgebraicCurve
variable {K F : Type*} [Field K] [Field F] [Algebra K F]
variable (K F) in
variable (K F) in
theorem regularDiffs_eq_span :
    regularDiffs K F = Submodule.span K {ω : Ω[F⁄K] | IsRegularDiff K F ω}
AlgebraicCurve.pullbackDiff

The map on Kähler differentials induced by the given homomorphism of function fields.

Source context 8 commands

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

noncomputable section
open KaehlerDifferential
namespace AlgebraicCurve
variable {K F : Type*} [Field K] [Field F] [Algebra K F]
variable (K F) in
variable (K F) in
section Pullback
variable {F' : Type*} [Field F'] [Algebra K F']
def pullbackDiff (φ : F →ₐ[K] F') : Ω[F⁄K] →ₗ[K] Ω[F'⁄K]
AlgebraicCurve.pullbackDiff_D
Source context 8 commands

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

noncomputable section
open KaehlerDifferential
namespace AlgebraicCurve
variable {K F : Type*} [Field K] [Field F] [Algebra K F]
variable (K F) in
variable (K F) in
section Pullback
variable {F' : Type*} [Field F'] [Algebra K F']
theorem pullbackDiff_D (φ : F →ₐ[K] F') (x : F) :
    pullbackDiff φ (D K F x) = D K F' (φ x)