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Add lean source and binary files (part 122)
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import OAI.Probability.GammaPassage.MeanLimit
import Mathlib.MeasureTheory.OuterMeasure.BorelCantelli
import Mathlib.Algebra.Order.Archimedean.Basic
namespace OAI
namespace GammaFPP
open MeasureTheory Filter Topology PlanarFPP
variable {Ω : Type*} [MeasurableSpace Ω] {P : Measure Ω}
/-- Summable deviations at the countable tolerances `1 / (k + 1)` imply
almost-sure convergence to zero. The events need not be measurable. -/
theorem ae_tendsto_zero_of_summable_deviations (X : ℕ → Ω → ℝ)
(hsum : ∀ k : ℕ,
(∑' n, P {ω | 1 / ((k : ℝ) + 1) ≤ |X n ω|}) ≠ ⊤) :
∀ᵐ ω ∂P, Tendsto (fun n => X n ω) atTop (𝓝 0) := by
have hall : ∀ᵐ ω ∂P, ∀ k : ℕ, ∀ᶠ n in atTop,
ω ∉ {ω | 1 / ((k : ℝ) + 1) ≤ |X n ω|} :=
ae_all_iff.mpr (fun k => ae_eventually_notMem (hsum k))
filter_upwards [hall] with ω hω
apply Metric.tendsto_nhds.mpr
intro ε hε
obtain ⟨k, hk⟩ := exists_nat_one_div_lt hε
filter_upwards [hω k] with n hn
have hn' : |X n ω| < 1 / ((k : ℝ) + 1) := lt_of_not_ge hn
simpa only [Real.dist_eq, sub_zero] using hn'.trans hk
/-- Add a convergent deterministic center after Borel--Cantelli. -/
theorem ae_tendsto_of_summable_centered_deviations
(X : ℕ → Ω → ℝ) (a : ℕ → ℝ) (L : ℝ)
(ha : Tendsto a atTop (𝓝 L))
(hsum : ∀ k : ℕ,
(∑' n, P {ω | 1 / ((k : ℝ) + 1) ≤ |X n ω - a n|}) ≠ ⊤) :
∀ᵐ ω ∂P, Tendsto (fun n => X n ω) atTop (𝓝 L) := by
filter_upwards [ae_tendsto_zero_of_summable_deviations
(fun n ω => X n ω - a n) hsum] with ω hω
simpa only [sub_add_cancel, zero_add] using hω.add ha
/-- Summable centered lattice-passage deviations identify the almost-sure
limit with the Fekete limit of the means. -/
theorem GammaEnvironment.ae_lattice_limit_of_summable_deviations
{τ : Edge → Ω → ℝ} {shape rate : ℝ}
(h : GammaEnvironment shape rate P τ) (hs : 0 < shape) (hr : 0 < rate)
(z : Vertex)
(hsum : ∀ k : ℕ, (∑' n : ℕ, P {ω |
1 / ((k : ℝ) + 1) ≤
|passageTime (fun e => τ e ω) 0 (n • z) / (n : ℝ) -
meanPassageSequence P τ z n / (n : ℝ)|}) ≠ ⊤) :
∀ᵐ ω ∂P, Tendsto
(fun n : ℕ => passageTime (fun e => τ e ω) 0 (n • z) / (n : ℝ))
atTop (𝓝 (directionalMeanConstant h hs hr z)) :=
ae_tendsto_of_summable_centered_deviations _ _ _
(h.meanPassageSequence_tendsto hs hr z) hsum
end GammaFPP
end OAI