OAI/Probability/SLE/Gauge/RandomPassageBounds.lean

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5 declarations, 0 contain sorry, 0 declared as axioms

Quantitative passage bounds for measurable random stopped charts and finite stopped changes of measure. These are integration identities, with the actual section estimates supplied by the ribbon proof.

  1. lemma OAI.SLEExactGauge.measurable_random_finiteBoundaryPath line 26
  2. lemma OAI.SLEExactGauge.measurableSet_random_finite_frontMassEvent line 35
  3. lemma OAI.SLEExactGauge.restart_condLExp_event_sections line 45
  4. theorem OAI.SLEExactGauge.restart_event_lower_bound line 75

    Source documentation

    Uniform section bounds integrate on every event in the stopped past. No countable list of possible pasts and no independence of steps is used.

    theorem restart_event_lower_bound
        {Ω X : Type*} [mΩ : MeasurableSpace Ω] [mX : MeasurableSpace X]
        (P : Measure Ω) [IsFiniteMeasure P] (ν : Measure X) [IsFiniteMeasure ν]
        (m : MeasurableSpace Ω) (hm : m ≤ mΩ)
        (Y : Ω → X) (hY : Measurable[mΩ] Y)
        (hlaw : ∀ A : Set Ω, MeasurableSet[m] A →
          @Measure.map Ω X mΩ mX Y (P.restrict A) = P A • ν)
        (C : Set (Ω × X)) (hC : @MeasurableSet (Ω × X) (m.prod mX) C)
        (E : Set Ω) (q : ℝ≥0∞)
        (hsections : ∀ᵐ ω ∂P, ω ∈ E → q ≤ ν {x | (ω, x) ∈ C})
        (A : Set Ω) (hA : MeasurableSet[m] A) (hAE : A ⊆ E) :
        q * P A ≤ P (A ∩ {ω | (ω, Y ω) ∈ C}) := by
    …
  5. theorem OAI.SLEExactGauge.normalizedDensity_event_lower_bound_of_condExp line 105

    Source documentation

    A lower bound on the density at a finite stop transfers any event observable there to the terminal tilted law.

    theorem normalizedDensity_event_lower_bound_of_condExp
        {Ω : Type*} [mΩ : MeasurableSpace Ω] (P : Measure Ω) [IsFiniteMeasure P]
        (m : MeasurableSpace Ω) (hm : m ≤ mΩ)
        (Z M : Ω → ℝ) (hZ : Integrable Z P) (hZpos : 0 ≤ᵐ[P] Z)
        (hM : M =ᵐ[P] P[Z | m])
        (a c : ℝ) (ha : 0 < a) (hc : 0 ≤ c)
        (E : Set Ω) (hE : MeasurableSet[m] E)
        (hbound : ∀ᵐ ω ∂P, ω ∈ E → c * a ≤ M ω) :
        ENNReal.ofReal c * P E ≤
          P.withDensity (fun ω => ENNReal.ofReal (Z ω / a)) E := by
    …