OAI/Analysis/LipschitzHilbert/Fourier/WitnessLineAverage.lean

GitHub source file

6 declarations, 0 contain sorry, 0 declared as axioms

The compact transferred witness gives the required popular line bin.

  1. def OAI.LipschitzHilbert.linePoint line 14
  2. def OAI.LipschitzHilbert.lineBinSet line 17
  3. theorem OAI.LipschitzHilbert.measurableSet_lineBinSet line 20
  4. theorem OAI.LipschitzHilbert.witness_projection_subset_lineBin line 28

    Source documentation

    A transferred witness has its entire horizontal projection inside the same measurable line bin.

    theorem witness_projection_subset_lineBin (E : Set (ℝ × ℝ))
        (u : ℝ × ℝ → ℝ) (s : ℝ) (z : ℝ × ℝ) (bin : Set ℝ)
        (htransfer : ∀ w ∈ E, u (SlopeBox.referencePoint s z w) ∈ bin) :
        Prod.fst '' E ⊆ lineBinSet u s z bin := by
    …

    Mentions: OAI.LipschitzHilbert.SlopeBox.referencePoint, OAI.LipschitzHilbert.lineBinSet

  5. theorem OAI.LipschitzHilbert.SlopeBox.witness_line_integral line 39

    Source documentation

    Turning the geometric transfer into an integral lower bound requires only the measurable bin and the actual compact witness.

    theorem witness_line_integral (T : SlopeBox) (E : Set (ℝ × ℝ)) (hE : IsCompact E)
        {A q : ℝ} (hA : 0 < A) (hbox : ∀ w ∈ E, T.radius w ≤ A)
        (harea : q * T.length * T.width ≤ (volume.prod volume).real E)
        (u : ℝ × ℝ → ℝ) (hu : Measurable u) (s : ℝ) (z : ℝ × ℝ)
        (bin I : Set ℝ) (hbin : MeasurableSet bin) (hIfinite : volume I ≠ ∞)
        (hproj : ∀ w ∈ E, w.1 ∈ I)
        (htransfer : ∀ w ∈ E, u (referencePoint s z w) ∈ bin) :
        q * T.length / (2 * A) ≤
          ∫ x in I, (lineBinSet u s z bin).indicator (fun _ => (1 : ℝ)) x := by
    …

    Mentions: OAI.LipschitzHilbert.SlopeBox, OAI.LipschitzHilbert.SlopeBox.referencePoint, OAI.LipschitzHilbert.lineBinSet

  6. theorem OAI.LipschitzHilbert.SlopeBox.witness_line_average line 60

    Source documentation

    The popular-bin threshold is the witness fraction divided only by the fixed geometric dilation factors.

    theorem witness_line_average (T : SlopeBox) (E : Set (ℝ × ℝ)) (hE : IsCompact E)
        {A q P : ℝ} (hA : 0 < A) (hq : 0 ≤ q) (hP : 0 < P)
        (hbox : ∀ w ∈ E, T.radius w ≤ A)
        (harea : q * T.length * T.width ≤ (volume.prod volume).real E)
        (u : ℝ × ℝ → ℝ) (hu : Measurable u) (s : ℝ) (z : ℝ × ℝ)
        (bin I : Set ℝ) (hbin : MeasurableSet bin) (hIfinite : volume I ≠ ∞)
        (hIpos : 0 < volume.real I) (hIlength : volume.real I ≤ P * T.length)
        (hproj : ∀ w ∈ E, w.1 ∈ I)
        (htransfer : ∀ w ∈ E, u (referencePoint s z w) ∈ bin) :
        q / (2 * A * P) ≤
          (∫ x in I, (lineBinSet u s z bin).indicator (fun _ => (1 : ℝ)) x) / volume.real I := by
    …

    Mentions: OAI.LipschitzHilbert.SlopeBox, OAI.LipschitzHilbert.SlopeBox.referencePoint, OAI.LipschitzHilbert.lineBinSet