Transport of minimal-prime support avoidance through localization #
For a finite module, localization commutes with its annihilator. The reverse inclusion uses a finite generating set to clear all denominators at once. Minimal-prime avoidance then follows from the ordinary minimal-prime correspondence for a localization.
theorem
AlgebraicAnalysis.LocalizedMinimalSupportAvoidance.annihilator_localizedModule
{C : Type u_1}
{E : Type u_2}
[CommRing C]
[AddCommGroup E]
[Module C E]
[Module.Finite C E]
(S : Submonoid C)
:
Module.annihilator (Localization S) (LocalizedModule S E) = Ideal.map (algebraMap C (Localization S)) (Module.annihilator C E)
The annihilator of a finite module commutes with localization.
theorem
AlgebraicAnalysis.LocalizedMinimalSupportAvoidance.localized_minimalPrime_avoids
{C : Type u_1}
{E : Type u_2}
[CommRing C]
[AddCommGroup E]
[Module C E]
[Module.Finite C E]
(S : Submonoid C)
(x : C)
(havoid : ∀ p ∈ (Module.annihilator C E).minimalPrimes, x ∉ p)
(Q : Ideal (Localization S))
:
Q ∈ (Module.annihilator (Localization S) (LocalizedModule S E)).minimalPrimes → (algebraMap C (Localization S)) x ∉ Q
Minimal-prime avoidance survives localization.