OAI/MeasureTheory/Falconer/Estimates/SuffixCollision.lean

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4 declarations, 0 contain sorry, 0 declared as axioms

The local collision estimate in the all-dimensional suffix step

A projection test on the entire second conditional cell controls every translated collision window. Quadratic distance linearization transfers that test to the original distance pushforward, before any cell grouping.

  1. theorem OAI.Falconer.projection_shifted_band_bound line 19
  2. theorem OAI.Falconer.affine_distance_collision line 42
  3. theorem OAI.Falconer.local_distance_collision_bound line 57
  4. theorem OAI.Falconer.suffix_cell_collision_bound line 84

    Source documentation

    The geometric hypotheses are supplied by the actual center separation and common child side, not by an abstract distance approximation.

    theorem suffix_cell_collision_bound (μ ν : Measure (Space d))
        [IsFiniteMeasure μ] [IsFiniteMeasure ν]
        (P Q : DyadicCube d) (hP : 0 < P.side) (hQ : Q.side = P.side)
        {g w : ℝ} (hg : 0 < g) (hsep : g ≤ ‖P.center-Q.center‖) (hw : 0 < w)
        (hsmall : 2*(d:ℝ)*P.side^2/g ≤ w) {H : ℝ≥0∞}
        (hproj : ((ν.restrict Q.carrier).prod (ν.restrict Q.carrier))
          {z : Space d × Space d |
            |inner ℝ (‖P.center-Q.center‖⁻¹ • (P.center-Q.center)) (z.1-z.2)| ≤ w} ≤ H) :
        (((μ.restrict P.carrier).prod (ν.restrict Q.carrier)).prod
          ((μ.restrict P.carrier).prod (ν.restrict Q.carrier)))
            {z | |dist z.1.1 z.1.2-dist z.2.1 z.2.2| ≤ w} ≤
          (μ P.carrier)^2 * (((PlanarFalconer.bandOffsets 3).card : ℝ≥0∞)*H) :=
    …

    Mentions: OAI.Falconer.Space, OAI.Falconer.DyadicCube, OAI.PlanarFalconer.bandOffsets