Documentation

BGW.StableTrees.SupremumCauchyDoob

Real compact Doob estimates for occupation differences #

The extended compact maximal inequality is converted to an integrable real supremum.

References #

theorem BGW.StableTrees.integral_sq_sup_Iic_le_four_mul {Ω : Type u_1} [MeasurableSpace Ω] {μ : MeasureTheory.Measure Ω} [MeasureTheory.IsFiniteMeasure μ] {ℱ : MeasureTheory.Filtration NNReal inst✝} {M : NNReal → Ω → ℝ} (hM : MeasureTheory.Martingale M ℱ μ) (hrc : ∀ (ω : Ω) (t : NNReal), ContinuousWithinAt (fun (s : NNReal) => M s ω) (Set.Ici t) t) (T : NNReal) (h2 : MeasureTheory.Integrable (fun (ω : Ω) => M T ω ^ 2) μ) :
MeasureTheory.Integrable (fun (ω : Ω) => (⨆ (t : ↑(Set.Iic T)), |M (↑t) ω|) ^ 2) μ ∧ ∫ (ω : Ω), (⨆ (t : ↑(Set.Iic T)), |M (↑t) ω|) ^ 2 ∂μ ≤ 4 * ∫ (ω : Ω), M T ω ^ 2 ∂μ

Real compact Doob inequality, with square integrability of the supremum.

theorem BGW.StableTrees.integral_sq_sup_occupationDiffMartingale_le {θ : ℝ} (hθ : 1 < θ ∧ θ ≤ 2) {ε η : ℝ} (hε : 0 < ε) (hη : 0 < η) {D : ℝ} (hD : ∀ (y : ℝ), |supOccupationResolvent θ 1 ε y - supOccupationResolvent θ 1 η y| ≤ D) (T : NNReal) :
MeasureTheory.Integrable (fun (f : Skorokhod.DLoc) => (⨆ (t : ↑(Set.Iic T)), |occupationDiffMartingale θ ε η (↑t) f|) ^ 2) ↑(stableLocalLaw θ) ∧ ∫ (f : Skorokhod.DLoc), (⨆ (t : ↑(Set.Iic T)), |occupationDiffMartingale θ ε η (↑t) f|) ^ 2 ∂↑(stableLocalLaw θ) ≤ 16 * D

Doob L² on compacts: a uniform resolvent difference bound controls the maximum.