noncomputable def
reynoldsOperator
{k : Type u_1}
[Field k]
{G : Type u_2}
[Group G]
[Fintype G]
{ι : Type u_3}
(algAct : G →* MvPolynomial ι k ≃ₐ[k] MvPolynomial ι k)
:
Instances For
theorem
reynolds_maps_to_invariants
{k : Type u_1}
[Field k]
[CharZero k]
{G : Type u_2}
[Group G]
[Fintype G]
[DecidableEq G]
{ι : Type u_3}
[Fintype ι]
[DecidableEq ι]
(algAct : G →* MvPolynomial ι k ≃ₐ[k] MvPolynomial ι k)
(h : MvPolynomial ι k)
:
theorem
reynolds_identity_on_invariants
{k : Type u_1}
[Field k]
[CharZero k]
{G : Type u_2}
[Group G]
[Fintype G]
[DecidableEq G]
{ι : Type u_3}
[Fintype ι]
[DecidableEq ι]
(algAct : G →* MvPolynomial ι k ≃ₐ[k] MvPolynomial ι k)
(h : MvPolynomial ι k)
(hh : h ∈ polynomialInvariantSubalgebra k G ι algAct)
:
noncomputable def
positiveInvariantIdeal
{k : Type u_1}
[Field k]
{G : Type u_3}
[Group G]
{ι : Type u_4}
(algAct : G →* MvPolynomial ι k ≃ₐ[k] MvPolynomial ι k)
:
Ideal (MvPolynomial ι k)
Instances For
theorem
reynolds_mul_invariant
{k : Type u_5}
[Field k]
[CharZero k]
{G : Type u_6}
[Group G]
[Fintype G]
[DecidableEq G]
{ι : Type u_7}
[Fintype ι]
[DecidableEq ι]
(algAct : G →* MvPolynomial ι k ≃ₐ[k] MvPolynomial ι k)
(h f : MvPolynomial ι k)
(hf : f ∈ polynomialInvariantSubalgebra k G ι algAct)
:
theorem
invariant_subalgebra_generated_by_ideal_generators
{k : Type u_1}
[Field k]
[CharZero k]
[IsAlgClosed k]
{G : Type u_3}
[Group G]
[Fintype G]
[DecidableEq G]
{ι : Type u_4}
[Fintype ι]
[DecidableEq ι]
(algAct : G →* MvPolynomial ι k ≃ₐ[k] MvPolynomial ι k)
(r : ℕ)
(f : Fin r → MvPolynomial ι k)
(hf_inv : ∀ (i : Fin r), f i ∈ polynomialInvariantSubalgebra k G ι algAct)
(hf_gen : positiveInvariantIdeal algAct = Ideal.span (Set.range f))
(hf_pos : ∀ (i : Fin r), 0 < (f i).totalDegree)
(h_deg_pres : ∀ (g : G) (p : MvPolynomial ι k), ((algAct g) p).totalDegree ≤ p.totalDegree)
(h_coeff_deg :
∀ q ∈ Ideal.span (Set.range f),
q ≠ 0 →
∃ (s : Fin r → MvPolynomial ι k),
q = ∑ i : Fin r, s i * f i ∧ ∀ (i : Fin r), s i ≠ 0 → (s i).totalDegree + (f i).totalDegree ≤ q.totalDegree)
:
noncomputable def
normPoly
{k : Type u_1}
[Field k]
{G : Type u_3}
[Group G]
[Fintype G]
{ι : Type u_4}
(algAct : G →* MvPolynomial ι k ≃ₐ[k] MvPolynomial ι k)
(x : MvPolynomial ι k)
:
Polynomial (MvPolynomial ι k)
Instances For
theorem
normPoly_eval_self
{k : Type u_1}
[Field k]
[CharZero k]
[IsAlgClosed k]
{G : Type u_3}
[Group G]
[Fintype G]
[DecidableEq G]
{ι : Type u_4}
[Fintype ι]
[DecidableEq ι]
(algAct : G →* MvPolynomial ι k ≃ₐ[k] MvPolynomial ι k)
(x : MvPolynomial ι k)
:
theorem
normPoly_monic
{k : Type u_1}
[Field k]
[CharZero k]
[IsAlgClosed k]
{G : Type u_3}
[Group G]
[Fintype G]
[DecidableEq G]
{ι : Type u_4}
[Fintype ι]
[DecidableEq ι]
(algAct : G →* MvPolynomial ι k ≃ₐ[k] MvPolynomial ι k)
(x : MvPolynomial ι k)
:
theorem
normPoly_coeff_invariant
{k : Type u_1}
[Field k]
[CharZero k]
[IsAlgClosed k]
{G : Type u_3}
[Group G]
[Fintype G]
[DecidableEq G]
{ι : Type u_4}
[Fintype ι]
[DecidableEq ι]
(algAct : G →* MvPolynomial ι k ≃ₐ[k] MvPolynomial ι k)
(x : MvPolynomial ι k)
(n : ℕ)
(h : G)
:
theorem
normPoly_coeffs_subset
{k : Type u_1}
[Field k]
[CharZero k]
[IsAlgClosed k]
{G : Type u_3}
[Group G]
[Fintype G]
[DecidableEq G]
{ι : Type u_4}
[Fintype ι]
[DecidableEq ι]
(algAct : G →* MvPolynomial ι k ≃ₐ[k] MvPolynomial ι k)
(x : MvPolynomial ι k)
:
theorem
isIntegral_over_invariants
{k : Type u_1}
[Field k]
[CharZero k]
[IsAlgClosed k]
{G : Type u_3}
[Group G]
[Fintype G]
[DecidableEq G]
{ι : Type u_4}
[Fintype ι]
[DecidableEq ι]
(algAct : G →* MvPolynomial ι k ≃ₐ[k] MvPolynomial ι k)
(x : MvPolynomial ι k)
:
IsIntegral (↥(polynomialInvariantSubalgebra k G ι algAct)) x
theorem
invariant_subalgebra_fg
{k : Type u_1}
[Field k]
[CharZero k]
[IsAlgClosed k]
{G : Type u_3}
[Group G]
[Fintype G]
[DecidableEq G]
{ι : Type u_4}
[Fintype ι]
[DecidableEq ι]
(algAct : G →* MvPolynomial ι k ≃ₐ[k] MvPolynomial ι k)
:
(polynomialInvariantSubalgebra k G ι algAct).FG
theorem
reynolds_diff_of_groupDiff_mem
{k : Type u_5}
[Field k]
[CharZero k]
{G : Type u_6}
[Group G]
[Fintype G]
[DecidableEq G]
{ι : Type u_7}
[Fintype ι]
[DecidableEq ι]
(algAct : G →* MvPolynomial ι k ≃ₐ[k] MvPolynomial ι k)
(p : MvPolynomial ι k)
(I : Ideal (MvPolynomial ι k))
(h_all : ∀ (w : G), (algAct w) p - p ∈ I)
:
theorem
positiveInvariantIdeal_stable
{k : Type u_5}
[Field k]
{G : Type u_6}
[Group G]
{ι : Type u_7}
(algAct : G →* MvPolynomial ι k ≃ₐ[k] MvPolynomial ι k)
(w : G)
(f : MvPolynomial ι k)
(hf : f ∈ positiveInvariantIdeal algAct)
:
theorem
list_prod_diff_mem_ideal
{k : Type u_5}
[Field k]
{G : Type u_6}
[Group G]
{ι : Type u_7}
(algAct : G →* MvPolynomial ι k ≃ₐ[k] MvPolynomial ι k)
(I : Ideal (MvPolynomial ι k))
(hstable : ∀ (w : G), ∀ f ∈ I, (algAct w) f ∈ I)
(p : MvPolynomial ι k)
(L : List G)
(hL : ∀ g ∈ L, (algAct g) p - p ∈ I)
:
theorem
algHom_sub_dvd_of_X_dvd
{ι : Type u_5}
[Fintype ι]
[DecidableEq ι]
{k : Type u_6}
[CommRing k]
(φ : MvPolynomial ι k →ₐ[k] MvPolynomial ι k)
(α : MvPolynomial ι k)
(hX : ∀ (i : ι), α ∣ φ (MvPolynomial.X i) - MvPolynomial.X i)
(p : MvPolynomial ι k)
:
theorem
reflection_hyperplane_linear_form
{k : Type u_5}
[Field k]
[CharZero k]
[IsAlgClosed k]
{V : Type u_6}
[AddCommGroup V]
[Module k V]
[FiniteDimensional k V]
{G : Type u_7}
[Group G]
[Fintype G]
[DecidableEq G]
{ι : Type u_8}
[Fintype ι]
[DecidableEq ι]
(ρ : G →* V ≃ₗ[k] V)
(algAct : G →* MvPolynomial ι k ≃ₐ[k] MvPolynomial ι k)
(σ : G)
(hσ : IsComplexReflection (ρ σ))
:
∃ (α : MvPolynomial ι k),
α ≠ 0 ∧ α.IsHomogeneous 1 ∧ α.totalDegree = 1 ∧ (∀ (i : ι), α ∣ (algAct σ) (MvPolynomial.X i) - MvPolynomial.X i) ∧ (∀ (i : ι) (d : ℕ),
(MvPolynomial.X i).IsHomogeneous d →
∀ (q : MvPolynomial ι k),
(algAct σ) (MvPolynomial.X i) - MvPolynomial.X i = q * α → q.IsHomogeneous (d - 1)) ∧ ∀ (p : MvPolynomial ι k) (d : ℕ),
p.IsHomogeneous d → ∀ (q : MvPolynomial ι k), (algAct σ) p - p = q * α → q.IsHomogeneous (d - 1)
theorem
reflection_hyperplane_divisibility
{k : Type u_5}
[Field k]
[CharZero k]
[IsAlgClosed k]
{V : Type u_6}
[AddCommGroup V]
[Module k V]
[FiniteDimensional k V]
{G : Type u_7}
[Group G]
[Fintype G]
[DecidableEq G]
{ι : Type u_8}
[Fintype ι]
[DecidableEq ι]
(ρ : G →* V ≃ₗ[k] V)
(algAct : G →* MvPolynomial ι k ≃ₐ[k] MvPolynomial ι k)
(σ : G)
(hσ : IsComplexReflection (ρ σ))
:
∃ (α : MvPolynomial ι k),
α ≠ 0 ∧ α.IsHomogeneous 1 ∧ α.totalDegree = 1 ∧ ∀ (p : MvPolynomial ι k),
∃ (q : MvPolynomial ι k), (algAct σ) p - p = q * α ∧ ∀ (d : ℕ), p.IsHomogeneous d → q.IsHomogeneous (d - 1)
theorem
reflection_divisibility_quotients
{k : Type u_5}
[Field k]
[CharZero k]
[IsAlgClosed k]
{V : Type u_6}
[AddCommGroup V]
[Module k V]
[FiniteDimensional k V]
{G : Type u_7}
[Group G]
[Fintype G]
[DecidableEq G]
{ι : Type u_8}
[Fintype ι]
[DecidableEq ι]
(ρ : G →* V ≃ₗ[k] V)
(algAct : G →* MvPolynomial ι k ≃ₐ[k] MvPolynomial ι k)
(m : ℕ)
(hm_pos : 0 < m)
(F g : Fin m → MvPolynomial ι k)
(hF_inv : ∀ (i : Fin m), F i ∈ polynomialInvariantSubalgebra k G ι algAct)
(_hF_homog : ∀ (i : Fin m), ∃ (d : ℕ), (F i).IsHomogeneous d)
(hg_homog : ∀ (i : Fin m), ∃ (d : ℕ), (g i).IsHomogeneous d)
(h_relation : ∑ i : Fin m, g i * F i = 0)
(σ : G)
(hσ : IsComplexReflection (ρ σ))
:
∃ (h : Fin m → MvPolynomial ι k),
∑ i : Fin m, h i * F i = 0 ∧ (∀ (i : Fin m), ∃ (d : ℕ), (h i).IsHomogeneous d) ∧ (∀ (i : Fin m), g i ≠ 0 → (g i).totalDegree ≥ 1 → (h i).totalDegree + 1 ≤ (g i).totalDegree) ∧ (h ⟨0, hm_pos⟩ ∈ positiveInvariantIdeal algAct →
(algAct σ) (g ⟨0, hm_pos⟩) - g ⟨0, hm_pos⟩ ∈ positiveInvariantIdeal algAct) ∧ (g ⟨0, hm_pos⟩ = 0 → (algAct σ) (g ⟨0, hm_pos⟩) - g ⟨0, hm_pos⟩ ∈ positiveInvariantIdeal algAct)
theorem
reynolds_invariant_pos_deg_mem_positiveInvariantIdeal
{k : Type u_1}
[Field k]
[CharZero k]
[IsAlgClosed k]
{V : Type u_2}
[AddCommGroup V]
[Module k V]
[FiniteDimensional k V]
{G : Type u_3}
[Group G]
[Fintype G]
[DecidableEq G]
{ι : Type u_4}
[Fintype ι]
[DecidableEq ι]
(ρ : G →* V ≃ₗ[k] V)
(algAct : G →* MvPolynomial ι k ≃ₐ[k] MvPolynomial ι k)
(_hG : IsComplexReflectionGroup G ρ)
(m : ℕ)
(hm_pos : 0 < m)
(F g : Fin m → MvPolynomial ι k)
(hF_inv : ∀ (i : Fin m), F i ∈ polynomialInvariantSubalgebra k G ι algAct)
(_hF_homog : ∀ (i : Fin m), ∃ (d : ℕ), (F i).IsHomogeneous d)
(_hg_homog : ∀ (i : Fin m), ∃ (d : ℕ), (g i).IsHomogeneous d)
(hF1_not_in_invG :
¬∃ (c : { j : Fin m // j ≠ ⟨0, hm_pos⟩ } → MvPolynomial ι k),
(∀ (i : { j : Fin m // j ≠ ⟨0, hm_pos⟩ }), c i ∈ polynomialInvariantSubalgebra k G ι algAct) ∧ F ⟨0, hm_pos⟩ = ∑ i : { j : Fin m // j ≠ ⟨0, hm_pos⟩ }, c i * F ↑i)
(h_relation : ∑ i : Fin m, g i * F i = 0)
:
theorem
reflection_single_diff_mem
{k : Type u_5}
[Field k]
[CharZero k]
[IsAlgClosed k]
{V : Type u_6}
[AddCommGroup V]
[Module k V]
[FiniteDimensional k V]
{G : Type u_7}
[Group G]
[Fintype G]
[DecidableEq G]
{ι : Type u_8}
[Fintype ι]
[DecidableEq ι]
(ρ : G →* V ≃ₗ[k] V)
(algAct : G →* MvPolynomial ι k ≃ₐ[k] MvPolynomial ι k)
(_hG : IsComplexReflectionGroup G ρ)
(m : ℕ)
(hm_pos : 0 < m)
(F g : Fin m → MvPolynomial ι k)
(hF_inv : ∀ (i : Fin m), F i ∈ polynomialInvariantSubalgebra k G ι algAct)
(hF_homog : ∀ (i : Fin m), ∃ (d : ℕ), (F i).IsHomogeneous d)
(hg_homog : ∀ (i : Fin m), ∃ (d : ℕ), (g i).IsHomogeneous d)
(_hF1_not_in_invG :
¬∃ (c : { j : Fin m // j ≠ ⟨0, hm_pos⟩ } → MvPolynomial ι k),
(∀ (i : { j : Fin m // j ≠ ⟨0, hm_pos⟩ }), c i ∈ polynomialInvariantSubalgebra k G ι algAct) ∧ F ⟨0, hm_pos⟩ = ∑ i : { j : Fin m // j ≠ ⟨0, hm_pos⟩ }, c i * F ↑i)
(h_relation : ∑ i : Fin m, g i * F i = 0)
(σ : G)
(hσ : IsComplexReflection (ρ σ))
(IH :
∀ (g' : Fin m → MvPolynomial ι k),
(∀ (i : Fin m), ∃ (d : ℕ), (g' i).IsHomogeneous d) →
∑ i : Fin m, g' i * F i = 0 →
(g' ⟨0, hm_pos⟩).totalDegree < (g ⟨0, hm_pos⟩).totalDegree → g' ⟨0, hm_pos⟩ ∈ positiveInvariantIdeal algAct)
:
theorem
reflection_group_diff_mem_positiveInvariantIdeal
{k : Type u_5}
[Field k]
[CharZero k]
[IsAlgClosed k]
{V : Type u_6}
[AddCommGroup V]
[Module k V]
[FiniteDimensional k V]
{G : Type u_7}
[Group G]
[Fintype G]
[DecidableEq G]
{ι : Type u_8}
[Fintype ι]
[DecidableEq ι]
(ρ : G →* V ≃ₗ[k] V)
(algAct : G →* MvPolynomial ι k ≃ₐ[k] MvPolynomial ι k)
(hG : IsComplexReflectionGroup G ρ)
(m : ℕ)
(hm_pos : 0 < m)
(F g : Fin m → MvPolynomial ι k)
(hF_inv : ∀ (i : Fin m), F i ∈ polynomialInvariantSubalgebra k G ι algAct)
(hF_homog : ∀ (i : Fin m), ∃ (d : ℕ), (F i).IsHomogeneous d)
(hg_homog : ∀ (i : Fin m), ∃ (d : ℕ), (g i).IsHomogeneous d)
(hF1_not_in_invG :
¬∃ (c : { j : Fin m // j ≠ ⟨0, hm_pos⟩ } → MvPolynomial ι k),
(∀ (i : { j : Fin m // j ≠ ⟨0, hm_pos⟩ }), c i ∈ polynomialInvariantSubalgebra k G ι algAct) ∧ F ⟨0, hm_pos⟩ = ∑ i : { j : Fin m // j ≠ ⟨0, hm_pos⟩ }, c i * F ↑i)
(h_relation : ∑ i : Fin m, g i * F i = 0)
(w : G)
:
theorem
reynolds_diff_mem_positiveInvariantIdeal
{k : Type u_1}
[Field k]
[CharZero k]
[IsAlgClosed k]
{V : Type u_2}
[AddCommGroup V]
[Module k V]
[FiniteDimensional k V]
{G : Type u_3}
[Group G]
[Fintype G]
[DecidableEq G]
{ι : Type u_4}
[Fintype ι]
[DecidableEq ι]
(ρ : G →* V ≃ₗ[k] V)
(algAct : G →* MvPolynomial ι k ≃ₐ[k] MvPolynomial ι k)
(hG : IsComplexReflectionGroup G ρ)
(m : ℕ)
(hm_pos : 0 < m)
(F g : Fin m → MvPolynomial ι k)
(hF_inv : ∀ (i : Fin m), F i ∈ polynomialInvariantSubalgebra k G ι algAct)
(hF_homog : ∀ (i : Fin m), ∃ (d : ℕ), (F i).IsHomogeneous d)
(hg_homog : ∀ (i : Fin m), ∃ (d : ℕ), (g i).IsHomogeneous d)
(hF1_not_in_invG :
¬∃ (c : { j : Fin m // j ≠ ⟨0, hm_pos⟩ } → MvPolynomial ι k),
(∀ (i : { j : Fin m // j ≠ ⟨0, hm_pos⟩ }), c i ∈ polynomialInvariantSubalgebra k G ι algAct) ∧ F ⟨0, hm_pos⟩ = ∑ i : { j : Fin m // j ≠ ⟨0, hm_pos⟩ }, c i * F ↑i)
(h_relation : ∑ i : Fin m, g i * F i = 0)
:
theorem
complex_reflection_syzygy_lemma
{k : Type u_1}
[Field k]
[CharZero k]
[IsAlgClosed k]
{V : Type u_2}
[AddCommGroup V]
[Module k V]
[FiniteDimensional k V]
{G : Type u_3}
[Group G]
[Fintype G]
[DecidableEq G]
{ι : Type u_4}
[Fintype ι]
[DecidableEq ι]
(ρ : G →* V ≃ₗ[k] V)
(algAct : G →* MvPolynomial ι k ≃ₐ[k] MvPolynomial ι k)
(hG : IsComplexReflectionGroup G ρ)
(m : ℕ)
(hm_pos : 0 < m)
(F g : Fin m → MvPolynomial ι k)
(hF_inv : ∀ (i : Fin m), F i ∈ polynomialInvariantSubalgebra k G ι algAct)
(hF_homog : ∀ (i : Fin m), ∃ (d : ℕ), (F i).IsHomogeneous d)
(hg_homog : ∀ (i : Fin m), ∃ (d : ℕ), (g i).IsHomogeneous d)
(hF1_not_in_invG :
¬∃ (c : { j : Fin m // j ≠ ⟨0, hm_pos⟩ } → MvPolynomial ι k),
(∀ (i : { j : Fin m // j ≠ ⟨0, hm_pos⟩ }), c i ∈ polynomialInvariantSubalgebra k G ι algAct) ∧ F ⟨0, hm_pos⟩ = ∑ i : { j : Fin m // j ≠ ⟨0, hm_pos⟩ }, c i * F ↑i)
(h_relation : ∑ i : Fin m, g i * F i = 0)
:
def
IsMinimalGeneratingSet
{k : Type u_1}
[Field k]
{ι : Type u_4}
(r : ℕ)
(f : Fin r → MvPolynomial ι k)
(I : Ideal (MvPolynomial ι k))
:
Instances For
theorem
pderiv_aeval_chain_rule
{k' : Type u_5}
[CommRing k']
{σ' : Type u_6}
{τ' : Type u_7}
[DecidableEq σ']
[Fintype σ']
(h : MvPolynomial σ' k')
(g : σ' → MvPolynomial τ' k')
(κ : τ')
:
(MvPolynomial.pderiv κ) ((MvPolynomial.aeval g) h) = ∑ j : σ', (MvPolynomial.aeval g) ((MvPolynomial.pderiv j) h) * (MvPolynomial.pderiv κ) (g j)
theorem
sum_X_mul_pderiv_eq
{k : Type u_1}
[Field k]
[CharZero k]
[IsAlgClosed k]
{ι : Type u_4}
[Fintype ι]
[DecidableEq ι]
(r : ℕ)
(f : Fin r → MvPolynomial ι k)
(d : Fin r → ℕ)
(a : Fin r → MvPolynomial ι k)
(b : Fin r → ι → MvPolynomial ι k)
(hf_homog : ∀ (j : Fin r), (f j).IsHomogeneous (d j))
(heq : ∀ (κ : ι), ∑ j : Fin r, a j * (MvPolynomial.pderiv κ) (f j) = ∑ j : Fin r, b j κ * f j)
:
theorem
quasi_homogeneous_wlog_homogeneity
{k : Type u_5}
[Field k]
[CharZero k]
[IsAlgClosed k]
{ι : Type u_6}
[Fintype ι]
[DecidableEq ι]
{r : ℕ}
(f : Fin r → MvPolynomial ι k)
(d : Fin r → ℕ)
(hf_homog : ∀ (j : Fin r), (f j).IsHomogeneous (d j))
(p : MvPolynomial (Fin r) k)
(hp : (MvPolynomial.aeval f) p = 0)
(hp_ne : p ≠ 0)
(i : Fin r)
:
∃ (dg : ℕ), (↑(d i) * (MvPolynomial.aeval f) ((MvPolynomial.pderiv i) p)).IsHomogeneous dg
theorem
euler_degree_argument_gives_membership
{k : Type u_5}
[Field k]
[CharZero k]
[IsAlgClosed k]
{ι : Type u_6}
[Fintype ι]
[DecidableEq ι]
{r : ℕ}
(hr_pos : 0 < r)
(f : Fin r → MvPolynomial ι k)
(d : Fin r → ℕ)
(hd_pos : ∀ (j : Fin r), 0 < d j)
(hf_homog : ∀ (j : Fin r), (f j).IsHomogeneous (d j))
(hf_min : IsMinimalGeneratingSet r f (Ideal.span (Set.range f)))
(a : Fin r → MvPolynomial ι k)
(h_euler : ∑ j : Fin r, ↑(d j) * a j * f j = 0)
(h_g0_in : ↑(d ⟨0, hr_pos⟩) * a ⟨0, hr_pos⟩ ∈ Ideal.span (Set.range f))
:
theorem
minimal_generators_algebraically_independent
{k : Type u_1}
[Field k]
[CharZero k]
[IsAlgClosed k]
{V : Type u_2}
[AddCommGroup V]
[Module k V]
[FiniteDimensional k V]
{G : Type u_3}
[Group G]
[Fintype G]
[DecidableEq G]
{ι : Type u_4}
[Fintype ι]
[DecidableEq ι]
(ρ : G →* V ≃ₗ[k] V)
(algAct : G →* MvPolynomial ι k ≃ₐ[k] MvPolynomial ι k)
(hG : IsComplexReflectionGroup G ρ)
(r : ℕ)
(f : Fin r → MvPolynomial ι k)
(d : Fin r → ℕ)
(hd_pos : ∀ (j : Fin r), 0 < d j)
(hf_homog : ∀ (j : Fin r), (f j).IsHomogeneous (d j))
(hf_inv : ∀ (i : Fin r), f i ∈ polynomialInvariantSubalgebra k G ι algAct)
(hf_min : IsMinimalGeneratingSet r f (positiveInvariantIdeal algAct))
:
noncomputable def
jacobianMatrixAt
{k : Type u_1}
[Field k]
{ι : Type u_3}
(y : ι → MvPolynomial ι k)
(u : ι → k)
:
Matrix ι ι k
Instances For
theorem
eval_algAct_eq_eval_actPoint
{k : Type u_1}
[Field k]
[CharZero k]
[IsAlgClosed k]
{G : Type u_2}
[Group G]
[Fintype G]
[DecidableEq G]
{ι : Type u_3}
[Fintype ι]
[DecidableEq ι]
(algAct : G →* MvPolynomial ι k ≃ₐ[k] MvPolynomial ι k)
(g : G)
(w : ι → k)
(f : MvPolynomial ι k)
:
(MvPolynomial.eval w) ((algAct g) f) = (MvPolynomial.eval fun (i : ι) => (MvPolynomial.eval w) ((algAct g) (MvPolynomial.X i))) f
theorem
mv_polynomial_disjoint_separation
{k : Type u_1}
[Field k]
[CharZero k]
[IsAlgClosed k]
{ι : Type u_3}
[Fintype ι]
[DecidableEq ι]
(S T : Finset (ι → k))
(hST : Disjoint S T)
:
∃ (p : MvPolynomial ι k), (∀ w ∈ S, (MvPolynomial.eval w) p = 0) ∧ ∀ w ∈ T, (MvPolynomial.eval w) p = 1
theorem
maximal_ideals_invariants_bij_orbits
{k : Type u_1}
[Field k]
[CharZero k]
[IsAlgClosed k]
{G : Type u_2}
[Group G]
[Fintype G]
[DecidableEq G]
{ι : Type u_3}
[Fintype ι]
[DecidableEq ι]
(algAct : G →* MvPolynomial ι k ≃ₐ[k] MvPolynomial ι k)
(u v : ι → k)
:
(∀ f ∈ polynomialInvariantSubalgebra k G ι algAct, (MvPolynomial.eval u) f = (MvPolynomial.eval v) f) ↔ ∃ (g : G), ∀ (i : ι), (MvPolynomial.eval v) ((algAct g) (MvPolynomial.X i)) = u i