Module

Exists_isAffineOpen_sup_eq_top.lean

Nyll.AlgebraicCurves.Models.Exists_isAffineOpen_sup_eq_top
1 declaration indexed from sourceView source ↗

Exists isAffineOpen sup eq top

A proper smooth integral curve admits a cover by two affine open subsets.

Declarations

AlgebraicCurve.exists_isAffineOpen_sup_eq_top
Source context 6 commands

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

section ProofImplementation
namespace AlgebraicCurves.Models.Proofs.Exists_isAffineOpen_sup_eq_top
attribute [-instance]
  AlgebraicCurve.Place.instIsScalarTowerSubtypeMemValuationSubringToValuationSubring
  AlgebraicCurve.Divisor.instDistribMulActionAlgEquiv AlgebraicCurve.Place.instSMulAlgEquiv
  AlgebraicCurve.Place.instIsPrincipalIdealRingSubtypeMemValuationSubringToValuationSubring
  AlgebraicCurve.Place.instIsDiscreteValuationRingSubtypeMemValuationSubringToValuationSubring
  AlgebraicCurve.Pic0.instDistribMulActionAlgEquiv
  AlgebraicCurve.Place.instAlgebraSubtypeMemValuationSubringToValuationSubring
  AlgebraicCurve.Place.instMulActionAlgEquiv AlgebraicCurve.Pic0.instSMulAlgEquiv
  AlgebraicCurve.CurveModel.isProper AlgebraicCurve.CurveModel.isIntegral
  AlgebraicCurve.CurveModel.smooth
attribute [-simp] AlgebraicCurve.Place.mk.injEq AlgebraicCurve.Divisor.degree_single
  AlgebraicCurve.Divisor.smul_single AlgebraicCurve.Place.smul_toValuationSubring
  AlgebraicCurve.Place.heightOneSpectrum_asIdeal AlgebraicCurve.Place.coe_algebraMap
  AlgebraicCurve.Place.ord_one AlgebraicCurve.Place.coe_smulRingEquiv_apply
  AlgebraicCurve.Pic0.coe_degZeroSMulHom AlgebraicCurve.Place.deg_smul
  AlgebraicCurve.Pic0.mk_zero AlgebraicCurve.Place.mk.sizeOf_spec
  AlgebraicCurve.Divisor.degree_smul AlgebraicCurve.Pic0.mk_add AlgebraicCurve.Place.ord_zero
  AlgebraicCurve.Place.ofHeightOneSpectrum_toValuationSubring AlgebraicCurve.CurveModel.mk.injEq
  AlgebraicCurve.CurveModel.mk.sizeOf_spec
universe u
open CategoryTheory CategoryTheory.Limits AlgebraicGeometry
theorem _root_.AlgebraicCurve.exists_isAffineOpen_sup_eq_top
    {K : Type u} [Field K] {C : Scheme.{u}} (c : C ⟶ Spec (CommRingCat.of K))
    [IsIntegral C] [IsProper c] [SmoothOfRelativeDimension 1 c]
    (haff : ∀ F : Finset C, ∃ U : C.Opens, IsAffineOpen U ∧ ∀ x ∈ F, x ∈ U) :
    ∃ U V : C.Opens, IsAffineOpen U ∧ IsAffineOpen V ∧ IsAffineOpen (U ⊓ V) ∧ U ⊔ V = ⊤