In a finite product of local `O`-algebras in which `π` is non-invertible, `π` lies in the Jacobson radical, and a componentwise regular element is regular.
ProvedTypeDensity.pi_algebraMap_mem_jacobson_bottype-density
In a finite product of local O-algebras in which π is non-invertible, π lies in the Jacobson radical, and a componentwise regular element is regular.
Preamble
import Definitions.Def_TypeDensity_Basic import Definitions.Def_TypeDensity_Measure_AdicCylinders import Definitions.Def_TypeDensity_Measure_HenselProducts import Theorems.Thm_TypeDensity_normalizing_factor_is_unit 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.Topology.Algebra.MvPolynomial import Mathlib.Algebra.Group.Pi.Units import Mathlib.Order.CompletePartialOrder import Mathlib.RingTheory.Henselian import Mathlib.RingTheory.Polynomial.Resultant.Basic import Mathlib.RingTheory.RegularLocalRing.Defs import Mathlib.RingTheory.SimpleRing.Principal set_option autoImplicit false open TypeDensity open MeasureTheory open scoped BigOperators ENNReal
Formal statement
theorem TypeDensity.pi_algebraMap_mem_jacobson_bot (O : Type) [CommRing O] (ι : Type) (C : ι → Type)
[∀ j, CommRing (C j)] [∀ j, Algebra O (C j)] [∀ j, IsLocalRing (C j)] (pi : O)
(hpi : ∀ j, algebraMap O (C j) pi ∈ IsLocalRing.maximalIdeal (C j)) (e : ∀ j, C j)
(he : ∀ j, Function.Injective (fun z : C j => e j * z)) :
algebraMap O (∀ j, C j) pi ∈ Ideal.jacobson (⊥ : Ideal (∀ j, C j)) ∧
Function.Injective (fun z : ∀ j, C j => e * z) := by sorrySource
TypeDensity/Measure/HenselProducts.lean#L779-L790