OAI/Geometry/RCD/Harmonic/HarmonicAffineImprovement.lean

GitHub source file

5 declarations, 0 contain sorry, 0 declared as axioms

Uniform affine improvement from published harmonic compactness

The threshold is uniform in the center, radius, coordinates and harmonic function. All inputs are measured approximation, a rescaled curvature bound, harmonicity and an actual normalized L² bound. The affine estimate itself is proved by a compactness contradiction.

  1. def OAI.RegularPointCoordinates.harmonicTargetNorm line 22

    Source documentation

    The averaged norm, with its radius dependence exposed for rescaling.

    def harmonicTargetNorm {K : ℝ} {n : ℕ} (hX : NoncollapsedRCD K n X)
        (p : X) (r : ℝ) (w : SobolevSpace (hausdorff n X) hX.quadratic) : ℝ :=
    …

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

  2. def OAI.RegularPointCoordinates.harmonicAffineResidualNorm line 29

    Source documentation

    The averaged affine residual, with its radius dependence exposed.

    def harmonicAffineResidualNorm {K : ℝ} {n : ℕ} (hX : NoncollapsedRCD K n X)
        (u : Fin n → SobolevSpace (hausdorff n X) hX.quadratic)
        (p : X) (r : ℝ) (w : SobolevSpace (hausdorff n X) hX.quadratic) : ℝ :=
    …

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

  3. structure OAI.RegularPointCoordinates.NormalizedHarmonicTest line 39

    Source documentation

    One normalized harmonic test on a measured almost-Euclidean ball.

    structure NormalizedHarmonicTest {K : ℝ} {n : ℕ}
        (hX : NoncollapsedRCD K n X) (S ε : ℝ) where
    …

    Mentions: OAI.RegularPointCoordinates.NoncollapsedRCD

  4. def OAI.RegularPointCoordinates.NormalizedHarmonicTest.residualNorm line 58
  5. theorem OAI.RegularPointCoordinates.harmonic_affine_improvement_of_measured_approximation line 67

    Source documentation

    The quantitative affine-improvement theorem for normalized harmonic functions. There is no energy-bound or affine-fit premise: the former is derived from Jiang's estimate and the latter from the Euclidean limit.

    theorem harmonic_affine_improvement_of_measured_approximation
        {K : ℝ} {n : ℕ} (hX : NoncollapsedRCD K n X) (hn : 2 ≤ n)
        (hcompact : LocalHarmonicMomentCompactnessInput hX)
        (hgradient : LocalHarmonicL2GradientInput hX)
        (heuclidean : EuclideanHarmonicHessianInput n) :
        ∃ m : ℕ, 3 ≤ m ∧ ∀ S : ℝ, 0 < S →
          ∃ ε : ℝ, 0 < ε ∧ ∀ d : NormalizedHarmonicTest hX S ε,
            d.residualNorm ((1 / 2 : ℝ) ^ m * S) <
              (1 / 2 : ℝ) * (1 / 2 : ℝ) ^ m * Real.sqrt ((1 / 2 : ℝ) ^ m) := by
    …

    Mentions: OAI.RegularPointCoordinates.NoncollapsedRCD, OAI.RegularPointCoordinates.LocalHarmonicMomentCompactnessInput, OAI.RegularPointCoordinates.LocalHarmonicL2GradientInput, OAI.RegularPointCoordinates.EuclideanHarmonicHessianInput, OAI.RegularPointCoordinates.NormalizedHarmonicTest