Continuous unit excursion height, including the terminal trace #
The shape/lifetime product supplies one deterministic scale whose unit shapes have continuous height versions. Raw scaling pulls that version back, including its zero at the lifetime.
theorem
BGW.StableTrees.exists_isExcursionHeightVersion_of_scale
(θ : ℝ)
(c : ↑(Set.Ioi 0))
(e : Excursion)
(hs : ∃ (g : C(NNReal, ℝ)), IsExcursionHeightVersion θ (excursionScale θ c e) g)
(hr :
∀ᵐ (s : ℝ) ∂MeasureTheory.volume.restrict (Set.Ioo 0 ↑e.lifetime), heightUniv θ (excursionScale θ c e).path ((↑c).toNNReal * s.toNNReal) = ↑c ^ (1 - 1 / θ) * heightUniv θ e.path s.toNNReal)
:
A version at a fixed scale pulls back whenever the raw heights obey the a.e.-age identity.
The positive lifetime mixing measure is nonzero for a valid stable index.
Under the unit excursion law (singular w.r.t. N) every excursion has an a.e.-age height
version, including the vanishing at the lifetime 1.
theorem
BGW.StableTrees.ae_heightPrefixAE_unitExcursionLaw
{θ : ℝ}
(hθ : 1 < θ ∧ θ ≤ 2)
:
∀ᵐ (e : Excursion) ∂↑(unitExcursionLaw θ), ∀ a < e.lifetime,
∀ (t : ↑(Set.Icc 0 ↑a)), (heightPrefixAE θ a (excursionRestrict a e)) t = (excursionHeight θ e) ⟨↑t, ⋯⟩
Graph identity under the unit law, simultaneously for all horizons a < ζ (ζ = 1
a.s.), with the same Borel map heightPrefixAE θ a.