OAI/AlgebraicGeometry/SurfaceCones/AffineModelRank.lean
17 declarations, 0 contain sorry, 0 declared as axioms
- abbrev
OAI.ExplicitCone.completedChartBaseMapline 13Source documentation
The genuine structure map of the distinguished affine chart of the literal eighteen-section ordinary blowup.
abbrev completedChartBaseMap : CommRingCat.of completedRing ⟶ CommRingCat.of completedBlowupChart := …Mentions: OAI.ExplicitCone.completedRing, OAI.ExplicitCone.completedBlowupChart
- lemma
OAI.ExplicitCone.completedChartBaseMap_injectiveline 17 - instance
OAI.ExplicitCone.completedBlowupExceptional_domainline 28 - instance
OAI.ExplicitCone.completedBlowupExceptional_primeline 32 - lemma
OAI.ExplicitCone.completedBlowupParameter_regularline 36 - abbrev
OAI.ExplicitCone.completedChartRestrictionSectionsline 43Source documentation
The exceptional-chart module is the restriction of the double dual of the pullback module to a prime Cartier divisor.
abbrev completedChartRestrictionSections (M : ModuleCat.{0} completedRing) := …Mentions: OAI.ExplicitCone.completedRing
- theorem
OAI.ExplicitCone.completedChartRestriction_torsionFreeline 54Source documentation
Torsion freedom is proved for the concrete exceptional module, not assumed as input to a numerical argument. There is no grading on M.
theorem completedChartRestriction_torsionFree (M : ModuleCat.{0} completedRing) [Module.Finite completedRing M] : Module.IsTorsionFree (completedBlowupChart ⧸ Ideal.span {completedBlowupParameter}) (completedChartRestrictionSections M) := …Mentions: OAI.ExplicitCone.completedRing, OAI.ExplicitCone.completedBlowupChart, OAI.ExplicitCone.completedBlowupParameter, OAI.ExplicitCone.completedChartRestrictionSections
- theorem
OAI.ExplicitCone.completedChartRestriction_rank_posline 62Source documentation
A nonzero finite torsion-free module gives positive rank on the exceptional affine section chart.
theorem completedChartRestriction_rank_pos (M : ModuleCat.{0} completedRing) [Module.Finite completedRing M] [Module.IsTorsionFree completedRing M] [Nontrivial M] : 0 < Module.finrank (completedBlowupChart ⧸ Ideal.span {completedBlowupParameter}) (completedChartRestrictionSections M) := by …Mentions: OAI.ExplicitCone.completedRing, OAI.ExplicitCone.completedBlowupChart, OAI.ExplicitCone.completedBlowupParameter, OAI.ExplicitCone.completedChartRestrictionSections
- abbrev
OAI.ExplicitCone.completedModelEline 80Source documentation
The literal double-dual extension for an arbitrary module on the completed cone, on the genuine proper Rees modification constructed above. This is not an assumed object with prescribed numerical invariants.
abbrev completedModelE (M : ModuleCat completedRing) : completedBlowup.Modules := …
Mentions: OAI.ExplicitCone.completedRing
- theorem
OAI.ExplicitCone.completedModelE_coherentline 85Source documentation
Coherence for EVERY finite module of the completed ring: no grading, algebra structure, or freeness premise is imposed on M.
theorem completedModelE_coherent (M : ModuleCat completedRing) [Module.Finite completedRing M] : (completedModelE M).IsFinitePresentation := by …Mentions: OAI.ExplicitCone.completedRing, OAI.ExplicitCone.completedModelE
- theorem
OAI.ExplicitCone.completedModelE_torsionFreeline 92Source documentation
Torsion freeness of the literal extension, proved on all open-section modules of the fixed integral model. No source regularity is assumed.
theorem completedModelE_torsionFree (M : ModuleCat completedRing) (U : completedBlowup.Opens) : @Module.IsTorsionFree Γ(completedBlowup, U) ((completedModelE M).val.obj (Opposite.op U)) _ _ ((completedModelE M).val.obj (Opposite.op U)).isModule := …Mentions: OAI.ExplicitCone.completedRing, OAI.ExplicitCone.completedBlowup, OAI.ExplicitCone.completedModelE
- theorem
OAI.ExplicitCone.completedModel_firstDual_coherentline 100Source documentation
The first dual in the same construction is also genuinely coherent.
theorem completedModel_firstDual_coherent (M : ModuleCat completedRing) [Module.Finite completedRing M] : (CoherentDual.homSheaf completedBlowup.sheaf ((Scheme.Modules.pullback completedBlowupMap).obj (tilde M)) (SheafOfModules.unit _)).IsFinitePresentation := by …Mentions: OAI.ExplicitCone.completedRing, OAI.CoherentDual.homSheaf, OAI.ExplicitCone.completedBlowupMap
- abbrev
OAI.ExplicitCone.completedExceptionalChartMapline 120Source documentation
The literal prime Cartier divisor in the distinguished actual blowup chart, embedded into the GLOBAL proper model.
abbrev completedExceptionalChartMap : Spec (.of (completedBlowupChart ⧸ Ideal.span {completedBlowupParameter})) ⟶ completedBlowup := …Mentions: OAI.ExplicitCone.completedBlowupChart, OAI.ExplicitCone.completedBlowupParameter, OAI.ExplicitCone.completedBlowup
- abbrev
OAI.ExplicitCone.completedGlobalRestrictionSectionsline 127Source documentation
Sections of the restriction of the GLOBALLY defined extension E.
abbrev completedGlobalRestrictionSections (M : ModuleCat.{0} completedRing) := …Mentions: OAI.ExplicitCone.completedRing
- def
OAI.ExplicitCone.completedGlobalRestrictionIsoline 134Source documentation
Compatibility with the actual global model; this closes the local/global identity left separate in the preceding positive-rank chart calculation.
def completedGlobalRestrictionIso (M : ModuleCat.{0} completedRing) : completedGlobalRestrictionSections M ≅ completedChartRestrictionSections M := by …Mentions: OAI.ExplicitCone.completedRing, OAI.ExplicitCone.completedGlobalRestrictionSections, OAI.ExplicitCone.completedChartRestrictionSections
- theorem
OAI.ExplicitCone.completedGlobalRestriction_torsionFreeline 148Source documentation
The actual global extension restricts to a torsion-free module along this whole exceptional chart, not merely its generic point.
theorem completedGlobalRestriction_torsionFree (M : ModuleCat.{0} completedRing) [Module.Finite completedRing M] : Module.IsTorsionFree (completedBlowupChart ⧸ Ideal.span {completedBlowupParameter}) (completedGlobalRestrictionSections M) := by …Mentions: OAI.ExplicitCone.completedRing, OAI.ExplicitCone.completedBlowupChart, OAI.ExplicitCone.completedBlowupParameter, OAI.ExplicitCone.completedGlobalRestrictionSections
- theorem
OAI.ExplicitCone.completedGlobalRestriction_rank_posline 157Source documentation
The restriction of the global double-dual extension has positive rank for every nonzero finite torsion-free module.
theorem completedGlobalRestriction_rank_pos (M : ModuleCat.{0} completedRing) [Module.Finite completedRing M] [Module.IsTorsionFree completedRing M] [Nontrivial M] : 0 < Module.finrank (completedBlowupChart ⧸ Ideal.span {completedBlowupParameter}) (completedGlobalRestrictionSections M) := by …Mentions: OAI.ExplicitCone.completedRing, OAI.ExplicitCone.completedBlowupChart, OAI.ExplicitCone.completedBlowupParameter, OAI.ExplicitCone.completedGlobalRestrictionSections