For monic `F, F'` with `Frac O[X]/(F) ≅ Frac O[X]/(F')`, `F` has type `σ` iff `F'` does.
ProvedTypeDensity.polynomial_type_algEquiv_ifftype-density
For monic F, F' with Frac O[X]/(F) ≅ Frac O[X]/(F'), F has type σ iff F' does.
Preamble
import Definitions.Def_TypeDensity_Basic import Definitions.Def_TypeDensity_Formula_LawAlgebra import Definitions.Def_TypeDensity_Algebra_AlgebraType import Definitions.Def_TypeDensity_Measure_AdicCylinders import Definitions.Def_TypeDensity_Measure_HenselProducts import Definitions.Def_TypeDensity_Unramified_Extension import Definitions.Def_TypeDensity_Measure_PrimitiveLocus import Definitions.Def_TypeDensity_Algebra_FactorInvariant import Theorems.Thm_TypeDensity_integral_closure_algEquiv import Theorems.Thm_TypeDensity_factor_invariant_algEquiv import Theorems.Thm_TypeDensity_monic_squarefree_factors_of_reduced import Theorems.Thm_TypeDensity_pi_fields_algEquiv_index_bijection import Theorems.Thm_TypeDensity_polynomial_quotient_product_equiv import Mathlib.FieldTheory.RatFunc.Basic import Mathlib.MeasureTheory.Measure.Haar.Unique import Mathlib.NumberTheory.ArithmeticFunction.Moebius import Mathlib.NumberTheory.Padics.PadicIntegers import Mathlib.RingTheory.IntegralClosure.IntegralRestrict import Mathlib.RingTheory.MvPowerSeries.Basic import Mathlib.RingTheory.RamificationInertia.Basic import Mathlib.Topology.Algebra.Nonarchimedean.AdicTopology import Mathlib.FieldTheory.Finite.GaloisField import Mathlib.RingTheory.AdicCompletion.Algebra import Mathlib.RingTheory.RegularLocalRing.Defs import Mathlib.RingTheory.Henselian import Mathlib.Topology.Algebra.MvPolynomial import Mathlib.Algebra.Group.Pi.Units import Mathlib.Order.CompletePartialOrder import Mathlib.RingTheory.Polynomial.Resultant.Basic import Mathlib.RingTheory.SimpleRing.Principal import Mathlib.Algebra.GroupWithZero.Submonoid.CancelMulZero import Mathlib.Algebra.Module.StablyFree.Basic import Mathlib.NumberTheory.Padics.RingHoms set_option autoImplicit false open TypeDensity open scoped ENNReal
Formal statement
theorem TypeDensity.polynomial_type_algEquiv_iff (O : Type) [CommRing O] [IsDomain O]
[IsDiscreteValuationRing O] [IsAdicComplete (IsLocalRing.maximalIdeal O) O]
[Finite (IsLocalRing.ResidueField O)] (F F' : Polynomial (BaseField O)) (hF : F.Monic)
(hF' : F'.Monic) (e : AdjoinRoot F ≃ₐ[BaseField O] AdjoinRoot F') (σ : FactorType) :
HasPolynomialTypeF O F σ ↔ HasPolynomialTypeF O F' σ := by sorrySource
TypeDensity/Unramified/PolynomialTypes.lean#L116-L122