OAI/Analysis/KadisonKastler/HilbertCoefficientMeasurable.lean
6 declarations, 0 contain sorry, 0 declared as axioms
Measurability from countably many Hilbert coefficients
The coefficients against a countable dense family give a continuous
injection into a countable product of copies of ℂ. Lusin–Souslin makes
this map a measurable embedding. Thus measurability of the coefficients
implies strong measurability, without assuming a Pettis theorem.
- theorem
OAI.KadisonKastler.aestronglyMeasurable_of_dense_innerline 28Source documentation
Countably many dense coefficient tests determine a measurable vector field.
theorem aestronglyMeasurable_of_dense_inner [Countable ι] (v : ι → H) (hv : DenseRange v) (f : D → H) (hf : ∀ i, AEStronglyMeasurable (fun x => inner ℂ (v i) (f x)) μ) : AEStronglyMeasurable f μ := by … - theorem
OAI.KadisonKastler.aestronglyMeasurable_of_countable_dense_innerline 44Source documentation
The same criterion stated using a countable dense subset.
theorem aestronglyMeasurable_of_countable_dense_inner (s : Set H) (hs : s.Countable) (hd : Dense s) (f : D → H) (hf : ∀ η ∈ s, AEStronglyMeasurable (fun x => inner ℂ η (f x)) μ) : AEStronglyMeasurable f μ := by … - theorem
OAI.KadisonKastler.aestronglyMeasurable_of_innerline 60Source documentation
In a separable Hilbert space, measurable scalar coefficients imply strong measurability of the vector field.
theorem aestronglyMeasurable_of_inner (f : D → H) (hf : ∀ η : H, AEStronglyMeasurable (fun x => inner ℂ η (f x)) μ) : AEStronglyMeasurable f μ := by … - theorem
OAI.KadisonKastler.operator_adjoint_eval_aestronglyMeasurableline 68Source documentation
Once a field has measurable evaluations, its adjoint does too. This uses the scalar adjoint identity and the preceding coefficient test.
theorem operator_adjoint_eval_aestronglyMeasurable (T : D → H →L[ℂ] H) (hT : ∀ ξ, AEStronglyMeasurable (fun x => T x ξ) μ) (η : H) : AEStronglyMeasurable (fun x => star (T x) η) μ := by … - theorem
OAI.KadisonKastler.operator_eval_aestronglyMeasurable_of_dense_coefficientsline 79Source documentation
Testing both variables only on a countable dense family suffices to make every evaluation of an operator field strongly measurable.
theorem operator_eval_aestronglyMeasurable_of_dense_coefficients [Countable ι] (v : ι → H) (hv : DenseRange v) (T : D → H →L[ℂ] H) (hT : ∀ i j, AEStronglyMeasurable (fun x => inner ℂ (v i) (T x (v j))) μ) (ξ : H) : AEStronglyMeasurable (fun x => T x ξ) μ := by … - theorem
OAI.KadisonKastler.operator_field_aestronglyMeasurable_of_dense_coefficientsline 95Source documentation
The two sets of measurable evaluations needed for the weak operator field C-star algebra follow from the same countable coefficient data.
theorem operator_field_aestronglyMeasurable_of_dense_coefficients [Countable ι] (v : ι → H) (hv : DenseRange v) (T : D → H →L[ℂ] H) (hT : ∀ i j, AEStronglyMeasurable (fun x => inner ℂ (v i) (T x (v j))) μ) : ∀ ξ, AEStronglyMeasurable (fun x => T x ξ) μ ∧ AEStronglyMeasurable (fun x => star (T x) ξ) μ := by …