OAI/Analysis/KadisonKastler/TomiyamaDenseProjections.lean
2 declarations, 0 contain sorry, 0 declared as axioms
Extension from projections to their norm-closed span
- theorem
OAI.KadisonKastler.closed_projection_span_eq_top_of_surjectiveline 16Source documentation
A surjective star homomorphism preserves norm-density of projection spans.
theorem closed_projection_span_eq_top_of_surjective (φ : A →⋆ₐ[ℂ] B) (hφ : Function.Surjective φ) (hdense : (Submodule.span ℂ {e : A | IsStarProjection e}).topologicalClosure = ⊤) : (Submodule.span ℂ {e : B | IsStarProjection e}).topologicalClosure = ⊤ := by … - theorem
OAI.KadisonKastler.tomiyama_map_mul_of_dense_projectionsline 38Source documentation
The algebraic projection identities extend to a target whose projections have norm-dense linear span.
theorem tomiyama_map_mul_of_dense_projections (hdense : (Submodule.span ℂ {e : B | IsStarProjection e}).topologicalClosure = ⊤) (φ : B →⋆ₐ[ℂ] A) (P : A →L[ℂ] B) (hP : ∀ x, ‖P x‖ ≤ ‖x‖) (hfix : ∀ b, P (φ b) = b) : (∀ b x, P (φ b * x) = b * P x) ∧ (∀ x b, P (x * φ b) = P x * b) := by …