Documentation

Atlas.NumberTheoryI.code.Chapter4.TensorSplitting

theorem TensorSplitting.span_prod_eq_biInf {R : Type u_1} [CommRing R] {ι : Type u_2} [DecidableEq ι] (s : Finset ι) (g : ιR) (hc : is, js, i jIsCoprime (g i) (g j)) :
Ideal.span {is, g i} = is, Ideal.span {g i}
theorem TensorSplitting.span_prod_eq_iInf {R : Type u_1} [CommRing R] {ι : Type u_2} [DecidableEq ι] [Fintype ι] (g : ιR) (hc : Pairwise fun (i j : ι) => IsCoprime (g i) (g j)) :
Ideal.span {i : ι, g i} = ⨅ (i : ι), Ideal.span {g i}
theorem TensorSplitting.quotientInfRingEquivPiQuotient_algebraMap {K' : Type u_1} [Field K'] {ι : Type u_2} [DecidableEq ι] [Fintype ι] (I : ιIdeal (Polynomial K')) (hc : Pairwise fun (i j : ι) => IsCoprime (I i) (I j)) (k : K') :
(Ideal.quotientInfRingEquivPiQuotient I hc) ((algebraMap K' (Polynomial K' ⨅ (i : ι), I i)) k) = (algebraMap K' ((i : ι) → Polynomial K' I i)) k
noncomputable def TensorSplitting.quotientInfAlgEquivPiQuotient {K' : Type u_1} [Field K'] {ι : Type u_2} [DecidableEq ι] [Fintype ι] (I : ιIdeal (Polynomial K')) (hc : Pairwise fun (i j : ι) => IsCoprime (I i) (I j)) :
(Polynomial K' ⨅ (i : ι), I i) ≃ₐ[K'] (i : ι) → Polynomial K' I i
Instances For
    noncomputable def TensorSplitting.adjoinRootProdAlgEquiv {K' : Type u_1} [Field K'] {ι : Type u_2} [DecidableEq ι] [Fintype ι] (g : ιPolynomial K') (hc : Pairwise fun (i j : ι) => IsCoprime (g i) (g j)) :
    AdjoinRoot (∏ i : ι, g i) ≃ₐ[K'] (i : ι) → AdjoinRoot (g i)
    Instances For
      noncomputable def TensorSplitting.adjoinRootProdAlgEquiv_of_irreducible {K' : Type u_1} [Field K'] {ι : Type u_2} [DecidableEq ι] [Fintype ι] (g : ιPolynomial K') (hirr : ∀ (i : ι), Irreducible (g i)) (hne : Pairwise fun (i j : ι) => ¬Associated (g i) (g j)) :
      AdjoinRoot (∏ i : ι, g i) ≃ₐ[K'] (i : ι) → AdjoinRoot (g i)
      Instances For
        Instances For
          noncomputable def TensorSplitting.adjoinRoot_tensor_algEquiv_prod {K : Type u_1} {K' : Type u_2} [Field K] [Field K'] [Algebra K K'] {ι : Type u_3} [DecidableEq ι] [Fintype ι] (f : Polynomial K) (_hf_irr : Irreducible f) (_hf_sep : f.Separable) (g : ιPolynomial K') (hirr : ∀ (i : ι), Irreducible (g i)) (hne : Pairwise fun (i j : ι) => ¬Associated (g i) (g j)) (hprod : Associated (Polynomial.map (algebraMap K K') f) (∏ i : ι, g i)) :
          TensorProduct K (AdjoinRoot f) K' ≃ₐ[K'] (i : ι) → AdjoinRoot (g i)
          Instances For