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151 lines
7.3 KiB
Text
151 lines
7.3 KiB
Text
import Mathlib.Order.KrullDimension
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import Mathlib.Order.JordanHolder
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import Mathlib.AlgebraicGeometry.PrimeSpectrum.Basic
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import Mathlib.Order.Height
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import Mathlib.RingTheory.Ideal.Basic
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import Mathlib.RingTheory.Ideal.Operations
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import Mathlib.LinearAlgebra.Finsupp
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import Mathlib.RingTheory.GradedAlgebra.Basic
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import Mathlib.RingTheory.GradedAlgebra.HomogeneousIdeal
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import Mathlib.Algebra.Module.GradedModule
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import Mathlib.RingTheory.Ideal.AssociatedPrime
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import Mathlib.RingTheory.Noetherian
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import Mathlib.RingTheory.Artinian
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import Mathlib.Algebra.Module.GradedModule
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import Mathlib.RingTheory.Noetherian
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import Mathlib.RingTheory.Finiteness
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import Mathlib.RingTheory.Ideal.Operations
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import Mathlib.AlgebraicGeometry.PrimeSpectrum.Basic
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import Mathlib.RingTheory.FiniteType
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import Mathlib.Order.Height
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import Mathlib.RingTheory.PrincipalIdealDomain
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import Mathlib.RingTheory.DedekindDomain.Basic
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import Mathlib.RingTheory.Ideal.Quotient
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import Mathlib.RingTheory.Localization.AtPrime
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import Mathlib.Order.ConditionallyCompleteLattice.Basic
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import Mathlib.Algebra.DirectSum.Ring
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import Mathlib.RingTheory.Ideal.LocalRing
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-- Setting for "library_search"
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set_option maxHeartbeats 0
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macro "ls" : tactic => `(tactic|library_search)
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-- New tactic "obviously"
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macro "obviously" : tactic =>
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`(tactic| (
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first
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| dsimp; simp; done; dbg_trace "it was dsimp simp"
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| simp; done; dbg_trace "it was simp"
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| tauto; done; dbg_trace "it was tauto"
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| simp; tauto; done; dbg_trace "it was simp tauto"
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| rfl; done; dbg_trace "it was rfl"
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| norm_num; done; dbg_trace "it was norm_num"
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| /-change (@Eq ℝ _ _);-/ linarith; done; dbg_trace "it was linarith"
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-- | gcongr; done
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| ring; done; dbg_trace "it was ring"
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| trivial; done; dbg_trace "it was trivial"
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-- | nlinarith; done
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| fail "No, this is not obvious."))
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-- @Definitions (to be classified)
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section
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noncomputable def length ( A : Type _) (M : Type _)
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[CommRing A] [AddCommGroup M] [Module A M] := Set.chainHeight {M' : Submodule A M | M' < ⊤}
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def HomogeneousPrime { A σ : Type _} [CommRing A] [SetLike σ A] [AddSubmonoidClass σ A] (𝒜 : ℤ → σ) [GradedRing 𝒜] (I : Ideal A):= (Ideal.IsPrime I) ∧ (Ideal.IsHomogeneous 𝒜 I)
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def HomogeneousMax { A σ : Type _} [CommRing A] [SetLike σ A] [AddSubmonoidClass σ A] (𝒜 : ℤ → σ) [GradedRing 𝒜] (I : Ideal A):= (Ideal.IsMaximal I) ∧ (Ideal.IsHomogeneous 𝒜 I)
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--theorem monotone_stabilizes_iff_noetherian :
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-- (∀ f : ℕ →o Submodule R M, ∃ n, ∀ m, n ≤ m → f n = f m) ↔ IsNoetherian R M := by
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-- rw [isNoetherian_iff_wellFounded, WellFounded.monotone_chain_condition]
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open GradedMonoid.GSmul
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open DirectSum
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instance tada1 (𝒜 : ℤ → Type _) (𝓜 : ℤ → Type _) [∀ i, AddCommGroup (𝒜 i)] [∀ i, AddCommGroup (𝓜 i)] [DirectSum.GCommRing 𝒜]
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[DirectSum.Gmodule 𝒜 𝓜] (i : ℤ ) : SMul (𝒜 0) (𝓜 i)
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where smul x y := @Eq.rec ℤ (0+i) (fun a _ => 𝓜 a) (GradedMonoid.GSmul.smul x y) i (zero_add i)
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lemma mylem (𝒜 : ℤ → Type _) (𝓜 : ℤ → Type _) [∀ i, AddCommGroup (𝒜 i)] [∀ i, AddCommGroup (𝓜 i)] [DirectSum.GCommRing 𝒜]
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[h : DirectSum.Gmodule 𝒜 𝓜] (i : ℤ) (a : 𝒜 0) (m : 𝓜 i) :
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of _ _ (a • m) = of _ _ a • of _ _ m := by
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refine' Eq.trans _ (Gmodule.of_smul_of 𝒜 𝓜 a m).symm
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refine' of_eq_of_gradedMonoid_eq _
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exact Sigma.ext (zero_add _).symm <| eq_rec_heq _ _
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instance tada2 (𝒜 : ℤ → Type _) (𝓜 : ℤ → Type _) [∀ i, AddCommGroup (𝒜 i)] [∀ i, AddCommGroup (𝓜 i)] [DirectSum.GCommRing 𝒜]
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[h : DirectSum.Gmodule 𝒜 𝓜] (i : ℤ ) : SMulWithZero (𝒜 0) (𝓜 i) := by
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letI := SMulWithZero.compHom (⨁ i, 𝓜 i) (of 𝒜 0).toZeroHom
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exact Function.Injective.smulWithZero (of 𝓜 i).toZeroHom Dfinsupp.single_injective (mylem 𝒜 𝓜 i)
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instance tada3 (𝒜 : ℤ → Type _) (𝓜 : ℤ → Type _) [∀ i, AddCommGroup (𝒜 i)] [∀ i, AddCommGroup (𝓜 i)] [DirectSum.GCommRing 𝒜]
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[h : DirectSum.Gmodule 𝒜 𝓜] (i : ℤ ): Module (𝒜 0) (𝓜 i) := by
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letI := Module.compHom (⨁ j, 𝓜 j) (ofZeroRingHom 𝒜)
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exact Dfinsupp.single_injective.module (𝒜 0) (of 𝓜 i) (mylem 𝒜 𝓜 i)
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-- Definition of a Hilbert function of a graded module
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noncomputable def hilbert_function (𝒜 : ℤ → Type _) (𝓜 : ℤ → Type _) [∀ i, AddCommGroup (𝒜 i)] [∀ i, AddCommGroup (𝓜 i)]
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[DirectSum.GCommRing 𝒜]
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[DirectSum.Gmodule 𝒜 𝓜] (hilb : ℤ → ℤ) := ∀ i, hilb i = (ENat.toNat (length (𝒜 0) (𝓜 i)))
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noncomputable def dimensionring { A: Type _}
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[CommRing A] := krullDim (PrimeSpectrum A)
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noncomputable def dimensionmodule ( A : Type _) (M : Type _)
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[CommRing A] [AddCommGroup M] [Module A M] := krullDim (PrimeSpectrum (A ⧸ ((⊤ : Submodule A M).annihilator)) )
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-- lemma graded_local (𝒜 : ℤ → Type _) [SetLike (⨁ i, 𝒜 i)] (𝓜 : ℤ → Type _) [∀ i, AddCommGroup (𝒜 i)] [∀ i, AddCommGroup (𝓜 i)]
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-- [DirectSum.GCommRing 𝒜]
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-- [DirectSum.Gmodule 𝒜 𝓜] (art: IsArtinianRing (𝒜 0)) (loc : LocalRing (𝒜 0)) : ∃ ( I : Ideal ((⨁ i, 𝒜 i))),(HomogeneousMax 𝒜 I) := sorry
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def PolyType (f : ℤ → ℤ) (d : ℕ) := ∃ Poly : Polynomial ℚ, ∃ (N : ℤ), ∀ (n : ℤ), N ≤ n → f n = Polynomial.eval (n : ℚ) Poly ∧ d = Polynomial.degree Poly
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end
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-- @[BH, 4.1.3] when d ≥ 1
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-- If M is a finite graed R-Mod of dimension d ≥ 1, then the Hilbert function H(M, n) is of polynomial type (d - 1)
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theorem hilbert_polynomial_ge1 (d : ℕ) (d1 : 1 ≤ d) (𝒜 : ℤ → Type _) (𝓜 : ℤ → Type _) [∀ i, AddCommGroup (𝒜 i)] [∀ i, AddCommGroup (𝓜 i)]
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[DirectSum.GCommRing 𝒜]
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[DirectSum.Gmodule 𝒜 𝓜] (art: IsArtinianRing (𝒜 0)) (loc : LocalRing (𝒜 0))
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(fingen : IsNoetherian (⨁ i, 𝒜 i) (⨁ i, 𝓜 i))
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(findim : dimensionmodule (⨁ i, 𝒜 i) (⨁ i, 𝓜 i) = d)
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(hilb : ℤ → ℤ) (Hhilb: hilbert_function 𝒜 𝓜 hilb)
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: PolyType hilb (d - 1) := by
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sorry
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-- @[BH, 4.1.3] when d = 0
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-- If M is a finite graed R-Mod of dimension zero, then the Hilbert function H(M, n) = 0 for n >> 0
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theorem hilbert_polynomial_0 (𝒜 : ℤ → Type _) (𝓜 : ℤ → Type _) [∀ i, AddCommGroup (𝒜 i)] [∀ i, AddCommGroup (𝓜 i)]
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[DirectSum.GCommRing 𝒜]
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[DirectSum.Gmodule 𝒜 𝓜] (art: IsArtinianRing (𝒜 0)) (loc : LocalRing (𝒜 0))
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(fingen : IsNoetherian (⨁ i, 𝒜 i) (⨁ i, 𝓜 i))
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(findim : dimensionmodule (⨁ i, 𝒜 i) (⨁ i, 𝓜 i) = 0)
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(hilb : ℤ → ℤ) (Hhilb : hilbert_function 𝒜 𝓜 hilb)
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: (∃ (N : ℤ), ∀ (n : ℤ), n ≥ N → hilb n = 0) := by
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sorry
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-- @[BH, 1.5.6 (b)(ii)]
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-- An associated prime of a graded R-Mod M is graded
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lemma Associated_prime_of_graded_is_graded
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(𝒜 : ℤ → Type _) (𝓜 : ℤ → Type _)
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[∀ i, AddCommGroup (𝒜 i)] [∀ i, AddCommGroup (𝓜 i)]
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[DirectSum.GCommRing 𝒜] [DirectSum.Gmodule 𝒜 𝓜]
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(p : associatedPrimes (⨁ i, 𝒜 i) (⨁ i, 𝓜 i))
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: true := by
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sorry
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-- Ideal.IsHomogeneous 𝒜 p
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-- @Existence of a chain of submodules of graded submoduels of f.g graded R-mod M
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lemma Exist_chain_of_graded_submodules (𝒜 : ℤ → Type _) (𝓜 : ℤ → Type _)
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[∀ i, AddCommGroup (𝒜 i)] [∀ i, AddCommGroup (𝓜 i)]
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[DirectSum.GCommRing 𝒜] [DirectSum.Gmodule 𝒜 𝓜]
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(fingen : IsNoetherian (⨁ i, 𝒜 i) (⨁ i, 𝓜 i))
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: true := by
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sorry
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