OAI/Geometry/RCD/Coordinates/ProjectionMeasuredCoordinates.lean

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3 declarations, 0 contain sorry, 0 declared as axioms

The actual metric coordinates on the projection ball

  1. theorem OAI.RegularPointCoordinates.radial_metric_from_controlled line 19

    Source documentation

    The controlled-normalization theorem uses a half-ball in units s/8. This is the same physical ball as the radial fit's radius-four ball in units s/64, with the exact corresponding error conversion.

    theorem radial_metric_from_controlled {n : ℕ} {p : X} {s epsilon : ℝ}
        (hs : 0 < s) (V : X → Euclidean n)
        (hf : IsPointedApproximation p 0 (s / 8) (1 / 2) epsilon
          (fun x => (s / 8)⁻¹ • V x)) :
        IsPointedApproximation p 0 (s / 64) 4 (8 * epsilon)
          (fun x => (s / 64)⁻¹ • V x) := by
    …

    Mentions: OAI.RegularPointCoordinates.Euclidean, OAI.RegularPointCoordinates.IsPointedApproximation

  2. theorem OAI.RegularPointCoordinates.projection_metric_rescale line 33

    Source documentation

    Restrict the centered metric map used by the radial fits and express it in the length units of the two-center projection.

    theorem projection_metric_rescale {n : ℕ} {p : X} {s delta : ℝ}
        (hs : 0 < s) (hdelta : 0 ≤ delta) (f : X → Euclidean n) (hcenter : f p = 0)
        (hf : IsPointedApproximation p 0 (s / 64) 4 delta f) :
        IsPointedApproximation p 0 s (2 * (1 / 1024)) (delta / 32)
          (fun x => (1 / 64 : ℝ) • f x) := by
    …

    Mentions: OAI.RegularPointCoordinates.Euclidean, OAI.RegularPointCoordinates.IsPointedApproximation

  3. theorem OAI.RegularPointCoordinates.projection_measured_coordinates line 84

    Source documentation

    The published measured-convergence input applies to the same centered coordinates used by the radial argument, at the fixed projection radius.

    theorem projection_measured_coordinates {K : ℝ} {n : ℕ}
        (hX : NoncollapsedRCD K n X) (hn : 2 ≤ n)
        (hmeasured : LocalMeasuredCoordinateInput hX) {epsilon : ℝ} (hepsilon : 0 < epsilon) :
        ∃ delta : ℝ, 0 < delta ∧ ∀ (p : X) (s : ℝ), 0 < s →
          -delta / 32 ≤ K * s ^ 2 →
          ∀ f : X → Euclidean n, Measurable f → f p = 0 →
            IsPointedApproximation p 0 (s / 64) 4 delta f →
            IsMeasuredEuclideanApproximation (hausdorff n X) n p s (1 / 1024) epsilon
              (fun x => (1 / 64 : ℝ) • f x) := by
    …

    Mentions: OAI.RegularPointCoordinates.NoncollapsedRCD, OAI.RegularPointCoordinates.LocalMeasuredCoordinateInput, OAI.RegularPointCoordinates.Euclidean, OAI.RegularPointCoordinates.IsPointedApproximation, OAI.RegularPointCoordinates.IsMeasuredEuclideanApproximation, OAI.RegularPointCoordinates.hausdorff