AlgebraicCurves.Divisors.Semilinear.Proofs.SemilinearConstantExtension.solution
Source context 3 commands
Surrounding namespaces, section variables, and local commands at this declaration.
section ProofImplementation
namespace AlgebraicCurves.Divisors.Semilinear.Proofs.SemilinearConstantExtension
open AlgebraicCurveLean source · statement
theorem solution
(K F K' F' : Type*)
[Field K] [Field F] [Field K'] [Field F'] [Algebra K F] [Algebra K' F']
[Algebra K K'] [Algebra F F'] [Algebra K F'] [IsScalarTower K K' F'] [IsScalarTower K F F']
[IsAlgClosed K] [CharZero K]
(hfg : ∃ x : F, Transcendental K x ∧ FiniteDimensional (IntermediateField.adjoin K ({x} : Set
F)) F)
(hfg' : ∃ x : F', Transcendental K' x ∧
FiniteDimensional (IntermediateField.adjoin K' ({x} : Set F')) F')
(hgen : IntermediateField.adjoin K' (Set.range (algebraMap F F')) = ⊤)
(S : Type*) [Group S] (galF : S →* SemilinearAut K F) (τ : S →* (K' ≃+* K'))
(hτ : ∀ (σ : S) (a : K), τ σ (algebraMap K K' a) = algebraMap K K' (SemilinearAut.baseAut (galF
σ) a)) :
∃! galF' : S →* SemilinearAut K' F',
(∀ (σ : S) (c : K'), SemilinearAut.baseAut (galF' σ) c = τ σ c) ∧
∀ (σ : S) (y : F), galF' σ • algebraMap F F' y = algebraMap F F' (galF σ • y)