OAI/AlgebraicGeometry/SurfaceCones/CompletedCartierNoetherian.lean

GitHub source file

80 declarations, 0 contain sorry, 0 declared as axioms

  1. lemma OAI.finiteType_of_sup_ranges line 7
  2. instance OAI.CompletedCartierChart.sourceAlgebra line 37
  3. instance OAI.CompletedCartierChart.sourceTower line 40
  4. instance OAI.CompletedCartierChart.finiteType line 43
  5. lemma OAI.CompletedCartierChart.noetherian line 47
  6. theorem OAI.RegularCartierLocal.spanFinrank_le_map_add_one line 64

    Source documentation

    Lifting a minimal generating set through a surjection with principal kernel adds at most one generator. No regularity hypothesis is hidden in this elementary embedding-dimension estimate.

    theorem spanFinrank_le_map_add_one (f : R →+* S) (hf : Function.Surjective f)
        (I : Ideal R) (hI : I.FG) (x : R) (hxI : x ∈ I)
        (hker : RingHom.ker f = Ideal.span {x}) :
        I.spanFinrank ≤ (I.map f).spanFinrank + 1 := by
    …
  7. theorem OAI.RegularCartierLocal.isRegularLocalRing_of_quotient line 104

    Source documentation

    A regular Cartier quotient of a Noetherian local ring lifts regularity to the ambient ring.

    theorem isRegularLocalRing_of_quotient [IsLocalRing R] [IsNoetherianRing R]
        (x : R) (hx : x ∈ maximalIdeal R) (hreg : IsSMulRegular R x)
        [IsRegularLocalRing (R ⧸ Ideal.span {x})] : IsRegularLocalRing R := by
    …
  8. theorem OAI.RegularCartierLocalization.regular_at_prime line 127

    Source documentation

    Every point of a regular effective principal divisor in a Noetherian integral scheme is a regular point of the ambient scheme.

    theorem regular_at_prime (x : R) (hx : x ≠ 0)
        [IsRegularRing (R ⧸ Ideal.span {x})]
        (p : Ideal R) [p.IsPrime] (hxp : x ∈ p) :
        IsRegularLocalRing (Localization.AtPrime p) := by
    …
  9. abbrev OAI.ExplicitCone.completedAffineChart line 162

    Source documentation

    The Cartier chart generated by the degreewise completed cone and the constants of its Proj basic open, inside the coefficient power-series ring.

    abbrev completedAffineChart := CompletedCartierChart.chart pieces sectionChart
    …

    Mentions: OAI.CompletedCartierChart.chart, OAI.ExplicitCone.pieces, OAI.ExplicitCone.sectionChart

  10. instance OAI.ExplicitCone.completedAffineCommRing line 165
  11. instance OAI.ExplicitCone.completedAffineRing line 166
  12. instance OAI.ExplicitCone.completedAffineSemiring line 167
  13. abbrev OAI.ExplicitCone.completedAffineSource line 169
  14. abbrev OAI.ExplicitCone.completedAffineParameter line 173
  15. theorem OAI.ExplicitCone.completedAffineSource_injective line 178
  16. theorem OAI.ExplicitCone.completedAffineParameter_ne_zero line 184
  17. instance OAI.ExplicitCone.completedAffine_finiteType line 189
  18. instance OAI.ExplicitCone.completedAffine_noetherian line 193
  19. def OAI.ExplicitCone.completedAffineExceptionalEquiv line 200

    Source documentation

    The exceptional divisor on the completed affine chart is isomorphic to the smooth chart of the projective section ring.

    def completedAffineExceptionalEquiv :
        (completedAffineChart ⧸ Ideal.span {completedAffineParameter}) ≃ₐ[ℂ] sectionChart :=
    …

    Mentions: OAI.ExplicitCone.completedAffineChart, OAI.ExplicitCone.completedAffineParameter, OAI.ExplicitCone.sectionChart

  20. instance OAI.ExplicitCone.completedAffineExceptional_regular line 206
  21. theorem OAI.ExplicitCone.completedAffine_regular_at_exceptional line 213

    Source documentation

    In particular every prime lying on its exceptional divisor is a genuine regular local ring of the algebraic completed-cone chart.

    theorem completedAffine_regular_at_exceptional (p : Ideal completedAffineChart) [p.IsPrime]
        (hp : completedAffineParameter ∈ p) : IsRegularLocalRing (Localization.AtPrime p) :=
    …

    Mentions: OAI.ExplicitCone.completedAffineChart, OAI.ExplicitCone.completedAffineParameter

  22. def OAI.ExplicitCone.completedChartMap line 226

    Source documentation

    The actual completed cone embeds in the formal Cartier chart over the literal z₀z₁z₄ section open. This does NOT assert that the formal chart is the uncompleted affine blowup base change.

    def completedChartMap : completedRing →ₐ[ℂ] PowerSeries sectionChart :=
    …

    Mentions: OAI.ExplicitCone.completedRing, OAI.ExplicitCone.sectionChart

  23. theorem OAI.ExplicitCone.completedChartMap_injective line 230
  24. lemma OAI.ExplicitCone.completedChartMap_coeff line 234
  25. def OAI.ExplicitCone.completedSection line 241

    Source documentation

    The original degree-one section, as an element of the degreewise completion used in MainClaim.

    def completedSection (i : Fin 6 × Fin 3) : completedRing :=
    …

    Mentions: OAI.ExplicitCone.completedRing

  26. lemma OAI.ExplicitCone.completedChartMap_section line 248
  27. lemma OAI.ExplicitCone.completedChartMap_baseSection line 263
  28. def OAI.FractionChartComparison.fieldMap line 278
  29. lemma OAI.FractionChartComparison.fieldMap_algebraMap line 287
  30. def OAI.FractionChartComparison.chart line 292

    Source documentation

    The literal fraction algebra of an ordinary blowup chart.

    def chart {ι : Type*} (s : ι → R) (t : R) : Subalgebra R (FractionRing R) :=
    …
  31. lemma OAI.FractionChartComparison.fieldMap_ratio line 296
  32. lemma OAI.FractionChartComparison.map_chart line 310
  33. def OAI.FractionChartComparison.chartEquiv line 327

    Source documentation

    A domain generated by actual section ratios is the actual fraction chart, not merely a ring agreeing with it modulo the exceptional equation.

    noncomputable def chartEquiv {ι : Type*} (s : ι → R) (t : R) (b : ι → B)
        (hf : Function.Injective (algebraMap R B)) (ht : t ≠ 0)
        (hb : ∀ i, b i * algebraMap R B t = algebraMap R B (s i))
        (hgen : Algebra.adjoin R (Set.range b) = ⊤) : chart s t ≃ₐ[R] B :=
    …

    Mentions: OAI.FractionChartComparison.chart

  34. lemma OAI.AlgebraGenerators.adjoin_of_sup_ranges line 339
  35. lemma OAI.CompletedCartierChart.adjoin_of_constants line 366
  36. abbrev OAI.ExplicitCone.completedAffineConstant line 378
  37. abbrev OAI.ExplicitCone.completedAffineRatio line 382
  38. lemma OAI.ExplicitCone.completedAffine_section line 385
  39. lemma OAI.ExplicitCone.completedAffine_baseSection line 391
  40. lemma OAI.ExplicitCone.completedSection_base_ne_zero line 396
  41. lemma OAI.ExplicitCone.sectionRatio_generates line 402
  42. lemma OAI.ExplicitCone.completedAffineRatio_generates line 414
  43. abbrev OAI.ExplicitCone.completedFractionChart line 422

    Source documentation

    The ordinary fraction chart for the original eighteen completed sections. This is the actual affine algebra R[s_i/s_00], not a formal tensor product.

    abbrev completedFractionChart := FractionChartComparison.chart completedSection
    …

    Mentions: OAI.FractionChartComparison.chart, OAI.ExplicitCone.completedSection

  44. def OAI.ExplicitCone.completedFractionChartEquiv line 427

    Source documentation

    The algebraic power-series realization coincides with the literal fraction chart of the blowup of the eighteen-section ideal.

    def completedFractionChartEquiv : completedFractionChart ≃ₐ[completedRing]
        completedAffineChart :=
    …

    Mentions: OAI.ExplicitCone.completedFractionChart, OAI.ExplicitCone.completedRing, OAI.ExplicitCone.completedAffineChart

  45. def OAI.ReesProj.homogeneous line 446

    Source documentation

    Degree-n polynomials inside the coefficient section algebra.

    def homogeneous (n : ℕ) : Submodule R (reesAlgebra I) where
    …
  46. lemma OAI.ReesProj.homogeneous_eq_monomial line 458
  47. instance OAI.ReesProj.homogeneousGradedMonoid line 467
  48. def OAI.ReesProj.homogeneousPart line 475
  49. lemma OAI.ReesProj.homogeneousPart_coe line 479
  50. def OAI.ReesProj.decomposePolynomial line 484

    Source documentation

    Finite support is the actual polynomial support, not an assumption of a formal infinite homogeneous decomposition.

    noncomputable def decomposePolynomial (p : reesAlgebra I) :
        ⨁ n, homogeneous I n :=
    …

    Mentions: OAI.ReesProj.homogeneous

  51. lemma OAI.ReesProj.decomposePolynomial_apply line 488
  52. lemma OAI.ReesProj.coeff_recompose line 500
  53. instance OAI.ReesProj.polynomialGradedRing line 515
  54. def OAI.ReesProj.proj line 535

    Source documentation

    The projective scheme of the section-coefficient algebra.

    noncomputable def proj : AlgebraicGeometry.Scheme :=
    …
  55. instance OAI.ReesProj.degreeZeroTower line 539
  56. instance OAI.ReesProj.finiteType_over_degreeZero line 544
  57. instance OAI.ReesProj.projProper line 548
  58. def OAI.ReesProj.zeroEquiv line 552

    Source documentation

    The degree-zero part of the actual Rees algebra is the original ring.

    def zeroEquiv : R ≃ₐ[R] homogeneous I 0 :=
    …

    Mentions: OAI.ReesProj.homogeneous

  59. lemma OAI.FractionChartComparison.ratio_mem_of_mem_span line 575
  60. lemma OAI.FractionChartComparison.scaled_mem_of_mem_power line 589
  61. def OAI.ReesProj.linearSection line 614

    Source documentation

    The actual degree-one Rees element associated to t ∈ I.

    def linearSection (t : R) (ht : t ∈ I) : reesAlgebra I :=
    …
  62. lemma OAI.ReesProj.linearSection_homogeneous line 617
  63. abbrev OAI.ReesProj.homogeneousChart line 622
  64. def OAI.ReesProj.evaluateOne line 625
  65. lemma OAI.ReesProj.evaluateOne_linearSection line 629
  66. lemma OAI.ReesProj.mapped_ne_zero line 635
  67. def OAI.ReesProj.homogeneousChartMap line 638
  68. lemma OAI.ReesProj.homogeneousChartMap_mk line 644
  69. lemma OAI.ReesProj.homogeneousChartMap_injective line 661
  70. lemma OAI.ReesProj.scaledCoefficient_mem_range line 685
  71. instance OAI.ReesProj.homogeneousChartScalarAlgebra line 698
  72. lemma OAI.ReesProj.homogeneousChartMap_scalar line 702
  73. def OAI.ReesProj.fractionChart line 728
  74. lemma OAI.ReesProj.ratio_mem_of_mem_span line 732
  75. lemma OAI.ReesProj.scaled_mem_of_mem_power line 747
  76. abbrev OAI.ReesProj.generatedChart line 764
  77. def OAI.ReesProj.generatedChartHom line 766
  78. lemma OAI.ReesProj.generatedChartHom_range line 770
  79. def OAI.ReesProj.generatedChartEquiv line 789

    Source documentation

    A literal Rees-Proj affine chart is the usual algebra of section fractions.

    def generatedChartEquiv : generatedChart s t ht ≃ₐ[R] fractionChart (K := K) s t :=
    …

    Mentions: OAI.ReesProj.generatedChart, OAI.ReesProj.fractionChart

  80. def OAI.ReesProj.basicOpenIsoFractionChart line 796