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https://github.com/GTBarkley/comm_alg.git
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commit
c2e808f243
1 changed files with 13 additions and 7 deletions
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@ -25,11 +25,11 @@ variable {R : Type _} [CommRing R] (I : PrimeSpectrum R)
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noncomputable def height : ℕ∞ := Set.chainHeight {J : PrimeSpectrum R | J < I}
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noncomputable def krullDim (R : Type) [CommRing R] : WithBot ℕ∞ := ⨆ (I : PrimeSpectrum R), height I
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noncomputable def krullDim (R : Type _) [CommRing R] : WithBot ℕ∞ := ⨆ (I : PrimeSpectrum R), height I
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lemma height_def : height I = Set.chainHeight {J : PrimeSpectrum R | J < I} := rfl
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lemma krullDim_def (R : Type) [CommRing R] : krullDim R = (⨆ (I : PrimeSpectrum R), height I : WithBot ℕ∞) := rfl
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lemma krullDim_def' (R : Type) [CommRing R] : krullDim R = iSup (λ I : PrimeSpectrum R => (height I : WithBot ℕ∞)) := rfl
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lemma krullDim_def (R : Type _) [CommRing R] : krullDim R = (⨆ (I : PrimeSpectrum R), height I : WithBot ℕ∞) := rfl
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lemma krullDim_def' (R : Type _) [CommRing R] : krullDim R = iSup (λ I : PrimeSpectrum R => (height I : WithBot ℕ∞)) := rfl
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noncomputable instance : CompleteLattice (WithBot (ℕ∞)) := WithBot.WithTop.completeLattice
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@ -42,13 +42,13 @@ lemma height_le_of_le {I J : PrimeSpectrum R} (I_le_J : I ≤ J) : height I ≤
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lemma krullDim_le_iff (R : Type _) [CommRing R] (n : ℕ) :
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krullDim R ≤ n ↔ ∀ I : PrimeSpectrum R, (height I : WithBot ℕ∞) ≤ ↑n := iSup_le_iff (α := WithBot ℕ∞)
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lemma krullDim_le_iff' (R : Type) [CommRing R] (n : ℕ∞) :
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lemma krullDim_le_iff' (R : Type _) [CommRing R] (n : ℕ∞) :
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krullDim R ≤ n ↔ ∀ I : PrimeSpectrum R, (height I : WithBot ℕ∞) ≤ ↑n := iSup_le_iff (α := WithBot ℕ∞)
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lemma le_krullDim_iff (R : Type) [CommRing R] (n : ℕ) :
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lemma le_krullDim_iff (R : Type _) [CommRing R] (n : ℕ) :
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n ≤ krullDim R ↔ ∃ I : PrimeSpectrum R, n ≤ (height I : WithBot ℕ∞) := by sorry
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lemma le_krullDim_iff' (R : Type) [CommRing R] (n : ℕ∞) :
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lemma le_krullDim_iff' (R : Type _) [CommRing R] (n : ℕ∞) :
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n ≤ krullDim R ↔ ∃ I : PrimeSpectrum R, n ≤ (height I : WithBot ℕ∞) := by sorry
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@[simp]
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@ -94,10 +94,16 @@ lemma dim_eq_bot_iff : krullDim R = ⊥ ↔ Subsingleton R := by
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. rw [h.forall_iff]
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trivial
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lemma krullDim_nonneg_of_nontrivial [Nontrivial R] : ∃ n : ℕ∞, Ideal.krullDim R = n := by
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lemma krullDim_nonneg_of_nontrivial (R : Type _) [CommRing R] [Nontrivial R] : ∃ n : ℕ∞, Ideal.krullDim R = n := by
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have h := dim_eq_bot_iff.not.mpr (not_subsingleton R)
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lift (Ideal.krullDim R) to ℕ∞ using h with k
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use k
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lemma dim_eq_zero_iff [Nontrivial R] : krullDim R = 0 ↔ ∀ I : PrimeSpectrum R, IsMaximal I.asIdeal := by
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constructor <;> intro h
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. intro I
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sorry
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. sorry
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@[simp]
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lemma field_prime_bot {K: Type _} [Field K] (P : Ideal K) : IsPrime P ↔ P = ⊥ := by
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