OAI/Analysis/OperatorAlgebra/ExpectationDensityRoots.lean
2 declarations, 0 contain sorry, 0 declared as axioms
Application of the hypertrace separation and Powers–Størmer estimates to an actual completely positive expectation.
- theorem
OAI.WeakPureInfiniteness.densityRoot_finite_supportline 16 - theorem
OAI.WeakPureInfiniteness.expectation_finite_density_rootsline 37Source documentation
A finite tracial expectation supplies positive finite-rank density roots of norm at most one, approximately invariant under the prescribed unitaries.
theorem expectation_finite_density_roots (M : VonNeumannAlgebra H) [PartialOrder M.toStarSubalgebra] [StarOrderedRing M.toStarSubalgebra] (τ : Pureness.TracialState M.toStarSubalgebra) (E : (H →L[ℂ] H) →L[ℂ] (H →L[ℂ] H)) (hE : CompletelyPositive E) (hEr : ∀ T, E T ∈ M) (hEf : ∀ T, T ∈ M → E T = T) (a : I → selfAdjoint M.toStarSubalgebra) (u : J → unitary M.toStarSubalgebra) {ε : ℝ} (hε : 0 < ε) : ∃ (n : ℕ) (w : Fin n → ℝ) (x : Fin n → H), (∀ k, 0 ≤ w k) ∧ (∑ k, w k = 1) ∧ (∀ k, ‖x k‖ ≤ 1) ∧ (∀ i, |(τ.functional (a i)).re - ∑ k, w k * (inner ℂ (x k) (((a i : M.toStarSubalgebra) : H →L[ℂ] H) (x k))).re| < ε) ∧ …Mentions: OAI.Pureness.TracialState, OAI.WeakPureInfiniteness.CompletelyPositive