OAI/Geometry/RCD/Metric/DyadicInteriorBalls.lean

GitHub source file

2 declarations, 0 contain sorry, 0 declared as axioms

Expanding interior balls and their volume factors

  1. theorem OAI.RegularPointCoordinates.expanding_radii line 14

    Source documentation

    Expanding radii have a dyadic gap available for a local mean estimate.

    theorem expanding_radii {R : ℝ} (hR : 0 < R) (i : ℕ) :
        0 < R/(4*2^i) ∧ R/(4*2^i) ≤ R ∧
        0 < R-R/(2*2^i) ∧ R-R/(2*2^i) < R ∧
        (R-R/(2*2^i))+R/(4*2^i) = R-R/(2*2^(i+1)) := by
    …
  2. theorem OAI.RegularPointCoordinates.NoncollapsedRCD.expanding_volume_factor line 33

    Source documentation

    The reciprocal volume cost grows by a fixed geometric factor.

    theorem NoncollapsedRCD.expanding_volume_factor {K : ℝ} {n : ℕ}
        (hX : NoncollapsedRCD K n X) (hn : 2 ≤ n) (p : X) (R : ℝ)
        (hR : 0 < R) (hcurv : -1 ≤ K*R^2) (i : ℕ) (q : X) (hq : dist q p ≤ R) :
        (hausdorff n X).real (ball p R) ≤
          ((8*Real.exp 4)^n*(2^n:ℝ)^i)*(hausdorff n X).real (ball q (R/(4*2^i))) := by
    …

    Mentions: OAI.RegularPointCoordinates.NoncollapsedRCD, OAI.RegularPointCoordinates.hausdorff