OAI/InformationTheory/AmplitudeDamping/SequentialProjections.lean
1 declarations, 0 contain sorry, 0 declared as axioms
- theorem
OAI.GAD.sequential_union_boundline 12Source documentation
The elementary sequential-projector union bound.
theorem sequential_union_bound {E : Type u_1} [NormedAddCommGroup E] [InnerProductSpace ℝ E] (P : ℕ → E → E) (hP : ∀ i x y, ⟪P i x, y-P i y⟫_ℝ = 0) (u : ℕ → E) (hu : ∀ i, u (i+1)=P i (u i)) (n : ℕ) : ‖u 0‖^2-‖u n‖^2 ≤ 4 * ∑ i ∈ Finset.range n, ‖u 0-P i (u 0)‖^2 := by …