import Mathlib import OAI.Analysis.Commutator.BicommutantRange import OAI.Analysis.Commutator.BiprodLinkColumn namespace OAI noncomputable section noncomputable section namespace Kadison.BiprodLinkColumn open HilbertBiprod PartialIsometryOrder variable {H G : Type*} [NormedAddCommGroup H] [InnerProductSpace ℂ H] [CompleteSpace H] [NormedAddCommGroup G] [InnerProductSpace ℂ G] [CompleteSpace G] variable {A : Type*} [CStarAlgebra A] lemma component_diagonal_intertwines (φ : A →⋆ₐ[ℂ] (H →L[ℂ] H)) (ψ : A →⋆ₐ[ℂ] (G →L[ℂ] G)) (h : Set.centralizer (Set.centralizer (Set.range (diagHom φ ψ)))=Set.range (diagHom φ ψ)) (v : Intertwiner (BicommutantRange.ofStarHom (diagHom φ ψ) h).commutant) (a : A) : (component _ v).comp (φ a)=(ψ a).comp (component _ v) := by apply component_intertwines _ φ ψ v a have hm : star v.val ∈ ((BicommutantRange.ofStarHom (diagHom φ ψ) h).commutant : Set _) := (BicommutantRange.ofStarHom (diagHom φ ψ) h).commutant.star_mem' v.mem rw [VonNeumannAlgebra.coe_commutant] at hm exact hm _ ⟨a,rfl⟩ end Kadison.BiprodLinkColumn end end end OAI