An ideal of a finite product of rings is determined by its images in the factors.
ProvedTypeDensity.pi_ideal_mem_iff_map_evaltype-density
An ideal of a finite product of rings is determined by its images in the factors.
Preamble
import Definitions.Def_TypeDensity_Basic import Definitions.Def_TypeDensity_Measure_AdicCylinders import Definitions.Def_TypeDensity_Measure_HenselProducts 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_ideal_mem_iff_map_eval (ι : Type) [Finite ι] (R : ι → Type) [∀ j, CommRing (R j)]
(I : Ideal (∀ j, R j)) :
(∀ x : ∀ j, R j, x ∈ I ↔ ∀ j, x j ∈ I.map (Pi.evalRingHom R j)) ∧ ∀ J : Ideal (∀ j, R j),
(∀ j, I.map (Pi.evalRingHom R j) = J.map (Pi.evalRingHom R j)) → I = J := by sorrySource
TypeDensity/Measure/HenselProducts.lean#L792-L815