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Modified some types to make them implicit

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This commit is contained in:
Sayantan Santra 2023-06-16 11:22:21 -07:00
parent 65d6e05f08
commit f76ff450e7
Signed by: SinTan1729
GPG key ID: EB3E68BFBA25C85F
1 changed files with 9 additions and 6 deletions
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CommAlg/krull.lean
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@ -49,10 +49,12 @@ lemma height_le_of_le {I J : PrimeSpectrum R} (I_le_J : I ≤ J) : height I ≤
show J' < J
exact lt_of_lt_of_le hJ' I_le_J
lemma krullDim_le_iff (R : Type _) [CommRing R] (n : ℕ) :
@[simp]
lemma krullDim_le_iff {R : Type _} [CommRing R] {n : ℕ} :
krullDim R ≤ n ↔ ∀ I : PrimeSpectrum R, (height I : WithBot ℕ∞) ≤ ↑n := iSup_le_iff (α := WithBot ℕ∞)
lemma krullDim_le_iff' (R : Type _) [CommRing R] (n : ℕ∞) :
@[simp]
lemma krullDim_le_iff' {R : Type _} [CommRing R] {n : ℕ∞} :
krullDim R ≤ n ↔ ∀ I : PrimeSpectrum R, (height I : WithBot ℕ∞) ≤ ↑n := iSup_le_iff (α := WithBot ℕ∞)
@[simp]
@ -91,7 +93,8 @@ lemma height_bot_eq {D: Type _} [CommRing D] [IsDomain D] : height (⊥ : PrimeS
/-- The Krull dimension of a ring being ≥ n is equivalent to there being an
ideal of height ≥ n. -/
lemma le_krullDim_iff (R : Type _) [CommRing R] (n : ℕ) :
@[simp]
lemma le_krullDim_iff {R : Type _} [CommRing R] {n : ℕ} :
n ≤ krullDim R ↔ ∃ I : PrimeSpectrum R, n ≤ (height I : WithBot ℕ∞) := by
constructor
· unfold krullDim
@ -246,7 +249,7 @@ lemma not_maximal_of_lt_prime {p : Ideal R} {q : Ideal R} (hq : IsPrime q) (h :
/-- Krull dimension is ≤ 0 if and only if all primes are maximal. -/
lemma dim_le_zero_iff : krullDim R ≤ 0 ↔ ∀ I : PrimeSpectrum R, IsMaximal I.asIdeal := by
show ((_ : WithBot ℕ∞) ≤ (0 : ℕ)) ↔ _
rw [krullDim_le_iff R 0]
rw [krullDim_le_iff]
constructor <;> intro h I
. contrapose! h
have ⟨𝔪, h𝔪⟩ := I.asIdeal.exists_le_maximal (IsPrime.ne_top I.IsPrime)
@ -353,7 +356,7 @@ lemma dim_le_one_iff : krullDim R ≤ 1 ↔ Ring.DimensionLEOne R := sorry
applies only to dimension zero rings and domains of dimension 1. -/
lemma dim_le_one_of_dimLEOne : Ring.DimensionLEOne R → krullDim R ≤ 1 := by
show _ → ((_ : WithBot ℕ∞) ≤ (1 : ℕ))
rw [krullDim_le_iff R 1]
rw [krullDim_le_iff]
intro H p
apply le_of_not_gt
intro h
@ -375,7 +378,7 @@ lemma dim_le_one_of_pid [IsDomain R] [IsPrincipalIdealRing R] : krullDim R ≤ 1
exact Ring.DimensionLEOne.principal_ideal_ring R
/-- The ring of polynomials over a field has dimension one. -/
lemma polynomial_over_field_dim_one {K : Type} [Nontrivial K] [Field K] : krullDim (Polynomial K) = 1 := by
lemma polynomial_over_field_dim_one {K : Type _} [Nontrivial K] [Field K] : krullDim (Polynomial K) = 1 := by
rw [le_antisymm_iff]
let X := @Polynomial.X K _
constructor