OAI/Probability/SLE/Geometry/FrontSuccessMeasurability.lean

GitHub source file

12 declarations, 0 contain sorry, 0 declared as axioms

Measurable actual front passages. Local ribbon coordinates are extended from their closed patch only to construct an adapted stopping time; on every successful passage this stopping time is exactly the original first front.

  1. def OAI.SLEExactGauge.FrontSuccessMeasurability.clampedPath line 21

    Source documentation

    Freeze a continuous path outside a finite time interval.

    def clampedPath (f : C(ℝ≥0, ℂ)) (s t : ℝ≥0) : C(ℝ≥0, ℂ) :=
    …
  2. theorem OAI.SLEExactGauge.FrontSuccessMeasurability.measurable_clampedPath line 24
  3. theorem OAI.SLEExactGauge.FrontSuccessMeasurability.sourceSausageSet_eq_clamped line 33
  4. theorem OAI.SLEExactGauge.FrontSuccessMeasurability.segmentSausageCharge_measurable line 48

    Source documentation

    Variable finite endpoints cause no measurability loss in the physical sausage charge. No stopping-time assumption on these endpoints is needed.

    theorem segmentSausageCharge_measurable
        {Ω : Type*} [MeasurableSpace Ω] (f : Ω → C(ℝ≥0, ℂ)) (hf : Measurable f)
        (s t : Ω → ℝ≥0) (hs : Measurable s) (ht : Measurable t)
        (κ v : ℝ) (R : Set ℂ) :
        Measurable (fun ω => segmentSausageCharge κ (f ω) (s ω) (t ω) v R) := by
    …

    Mentions: OAI.SLEExactGauge.segmentSausageCharge

  5. theorem OAI.SLEExactGauge.FrontSuccessMeasurability.measurableSet_prefix_mapsTo line 68

    Source documentation

    An open target and a measurable finite endpoint give a measurable whole-prefix containment event.

    theorem measurableSet_prefix_mapsTo
        {Ω : Type*} [MeasurableSpace Ω] (f : Ω → C(ℝ≥0, ℂ)) (hf : Measurable f)
        (t : Ω → ℝ≥0) (ht : Measurable t) (V : Set ℂ) (hV : IsOpen V) :
        MeasurableSet {ω | MapsTo (f ω) (Icc 0 (t ω)) V} := by
    …
  6. theorem OAI.SLEExactGauge.FrontSuccessMeasurability.firstFrontTime_eq_of_prefix line 94

    Source documentation

    Agreement through an attained first hit identifies the first hitting time, regardless of how the two coordinates are defined later.

    theorem firstFrontTime_eq_of_prefix
        (x y : ℝ≥0 → ℝ) (q : ℝ) (τ : ℝ≥0)
        (hx : firstFrontTime x q = (τ : WithTop ℝ≥0)) (hattain : x τ = q)
        (hxy : EqOn x y (Icc 0 τ)) :
        firstFrontTime y q = (τ : WithTop ℝ≥0) := by
    …
  7. theorem OAI.SLEExactGauge.FrontSuccessMeasurability.frontSuccess_eq_of_eqOn line 120

    Source documentation

    The concrete success event depends only on the coordinate inside its allowed region; the attained front equation makes this exact.

    theorem frontSuccess_eq_of_eqOn
        {Ω : Type*} (η : ℕ → Ω → ℝ≥0 → ℂ) (p p' : ℕ → ℂ → ℝ)
        (σ : Ω → ℝ≥0) (V : ℕ → Set ℂ) (a : ℕ → ℂ) (ε : ℝ) (n : ℕ)
        (hpeq : EqOn (p n) (p' n) (V n)) :
        FrontSuccess η p σ V a ε n = FrontSuccess η p' σ V a ε n := by
    …
  8. theorem OAI.SLEExactGauge.FrontSuccessMeasurability.firstFrontTime_stopping line 142

    Source documentation

    A globally continuous progress coordinate gives the actual adapted front stopping time, including the possibility of no hit.

    theorem firstFrontTime_stopping
        {Ω : Type*} [m : MeasurableSpace Ω] (ℱ : Filtration ℝ≥0 m)
        (η : Ω → ℝ≥0 → ℂ) (ha : Adapted ℱ (fun t ω => η ω t))
        (hc : ∀ ω, Continuous (η ω)) (p : ℂ → ℝ) (hp : Continuous p) :
        IsStoppingTime ℱ (fun ω => firstFrontTime (fun t => p (η ω t)) 1) :=
    …
  9. theorem OAI.SLEExactGauge.FrontSuccessMeasurability.measurableSet_frontSuccess_of_continuous line 152

    Source documentation

    Success is measurable when the progress coordinate is globally continuous; the next theorem removes this unnecessary global requirement.

    theorem measurableSet_frontSuccess_of_continuous
        {Ω : Type*} [m : MeasurableSpace Ω] (ℱ : Filtration ℝ≥0 m)
        (η : ℕ → Ω → ℝ≥0 → ℂ) (p : ℕ → ℂ → ℝ) (σ : Ω → ℝ≥0)
        (V : ℕ → Set ℂ) (a : ℕ → ℂ) (ε : ℝ) (n : ℕ)
        (ha : Adapted ℱ (fun t ω => η n ω t)) (hc : ∀ ω, Continuous (η n ω))
        (hp : Continuous (p n)) (hσ : Measurable σ) (hV : IsOpen (V n)) :
        MeasurableSet (FrontSuccess η p σ V a ε n) := by
    …
  10. theorem OAI.SLEExactGauge.FrontSuccessMeasurability.exists_continuous_progress_extension line 181

    Source documentation

    A closed physical ribbon patch supplies a continuous progress extension by the proved Tietze theorem.

    theorem exists_continuous_progress_extension
        (p : ℂ → ℝ) (K : Set ℂ) (hK : IsClosed K) (hp : ContinuousOn p K) :
        ∃ g : C(ℂ, ℝ), EqOn p g K := by
    …
  11. theorem OAI.SLEExactGauge.FrontSuccessMeasurability.measurableSet_frontSuccess_of_continuousOn line 193

    Source documentation

    The original local front event is measurable, and agrees there with an adapted front stopping time obtained by extending the ribbon coordinate.

    theorem measurableSet_frontSuccess_of_continuousOn
        {Ω : Type*} [m : MeasurableSpace Ω] (ℱ : Filtration ℝ≥0 m)
        (η : ℕ → Ω → ℝ≥0 → ℂ) (p : ℕ → ℂ → ℝ) (σ : Ω → ℝ≥0)
        (V : ℕ → Set ℂ) (a : ℕ → ℂ) (ε : ℝ) (n : ℕ)
        (ha : Adapted ℱ (fun t ω => η n ω t)) (hc : ∀ ω, Continuous (η n ω))
        (K : Set ℂ) (hK : IsClosed K) (hp : ContinuousOn (p n) K)
        (hσ : Measurable σ) (hV : IsOpen (V n)) (hVK : V n ⊆ K) :
        MeasurableSet (FrontSuccess η p σ V a ε n) ∧
          ∃ ρ : Ω → WithTop ℝ≥0, IsStoppingTime ℱ ρ ∧
            ∀ ω ∈ FrontSuccess η p σ V a ε n,
              ρ ω = firstFrontTime (fun t => p n (η n ω t)) 1 := by
    …
  12. theorem OAI.SLEExactGauge.FrontSuccessMeasurability.measurableSet_frontSuccess_mass line 218

    Source documentation

    The full local-coordinate success-and-mass event is measurable. This is the concrete event used by the repeated ribbon passage argument.

    theorem measurableSet_frontSuccess_mass
        {Ω : Type*} [m : MeasurableSpace Ω] (ℱ : Filtration ℝ≥0 m)
        (η : ℕ → Ω → ℝ≥0 → ℂ) (p : ℕ → ℂ → ℝ) (σ : Ω → ℝ≥0)
        (V : ℕ → Set ℂ) (a : ℕ → ℂ) (ε : ℝ) (n : ℕ)
        (ha : Adapted ℱ (fun t ω => η n ω t)) (hc : ∀ ω, Continuous (η n ω))
        (K : Set ℂ) (hK : IsClosed K) (hp : ContinuousOn (p n) K)
        (hσ : Measurable σ) (hV : IsOpen (V n)) (hVK : V n ⊆ K)
        (κ v c : ℝ) (R : Set ℂ) :
        MeasurableSet {ω | ω ∈ FrontSuccess η p σ V a ε n ∧ ENNReal.ofReal c ≤
          segmentSausageCharge κ (η n ω) (σ ω)
            (frontTime (fun t => p n (η n ω t)) 1) v R} := by
    …

    Mentions: OAI.SLEExactGauge.segmentSausageCharge