Mean convergence of weighted boundary potentials #
Compact square-mean occupation errors and the half-rate potential bound control the weighted cumulative error before identifying the exact mean potential.
theorem
BGW.StableTrees.ae_supBoundaryPotential_cumulative
{θ : ℝ}
(hθ : 1 < θ ∧ θ ≤ 2)
{q lam : ℝ}
(hq : 0 < q)
(hlam : 0 ≤ lam)
:
∀ᵐ (f : Skorokhod.DLoc) ∂↑(stableLocalLaw θ), have J := ∫ (s : ℝ) in Set.Ioi 0, supAuxLocalTime θ f s.toNNReal ∂(supWeightStieltjes q lam ⋯ hlam f).measure;
supBoundaryPotential θ q lam f = ENNReal.ofReal J ∧ (supBoundaryPotential θ q lam f).toReal = J ∧ J ≤ supAuxDiscountedTail θ (q / 2) 0 f
The boundary potential has a finite cumulative representative bounded by the half-rate auxiliary potential.
Reference: Bertoin, Lévy Processes, Chapter VI.
theorem
BGW.StableTrees.integrable_supBoundaryPotential_toReal
{θ : ℝ}
(hθ : 1 < θ ∧ θ ≤ 2)
{q lam : ℝ}
(hq : 0 < q)
(hlam : 0 ≤ lam)
:
MeasureTheory.Integrable (fun (f : Skorokhod.DLoc) => (supBoundaryPotential θ q lam f).toReal) ↑(stableLocalLaw θ)
The real boundary potential is integrable at positive time rate.
Reference: Bertoin, Lévy Processes, Chapter VI.