OAI/Geometry/RCD/Harmonic/HarmonicMeanValueInput.lean

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2 declarations, 0 contain sorry, 0 declared as axioms

The published harmonic mean-value estimate used for affine evaluation

Jiang, Cheeger-harmonic functions in metric measure spaces revisited, JFA 266 (2014), Lemma 4.1 (printed pp.14–15), with lambda=0 and exponent 2. Only the half-ball L-infinity consequence under bounded rescaled curvature is retained. Full support and continuity give pointwise evaluation below.

  1. def OAI.RegularPointCoordinates.LocalHarmonicL2MeanValueInput line 21

    Source documentation

    The fixed-ratio, harmonic L²-to-L∞ specialization of Jiang Lemma 4.1.

    def LocalHarmonicL2MeanValueInput {K : ℝ} {n : ℕ} (hX : NoncollapsedRCD K n X) : Prop :=
    …

    Mentions: OAI.RegularPointCoordinates.NoncollapsedRCD

  2. theorem OAI.RegularPointCoordinates.LocalHarmonicL2MeanValueInput.center_bound line 30

    Source documentation

    The a.e. estimate applies at the center to every continuous representative.

    theorem LocalHarmonicL2MeanValueInput.center_bound {K : ℝ} {n : ℕ}
        {hX : NoncollapsedRCD K n X} (hmean : LocalHarmonicL2MeanValueInput hX)
        (hn : 2 ≤ n) {a : ℝ} (ha : 0 ≤ a) :
        ∃ C : ℝ, 1 ≤ C ∧ ∀ (p : X) (r : ℝ), 0 < r → -a ≤ K * r ^ 2 →
        ∀ (w : SobolevSpace (hausdorff n X) hX.quadratic) (v : X → ℝ),
          IsSobolevHarmonicOn (hausdorff n X) hX.quadratic (ball p r) w →
          ContinuousOn v (ball p r) →
          (SobolevSpace.toLp (hausdorff n X) hX.quadratic w =ᵐ[
            (hausdorff n X).restrict (ball p r)] v) →
          |v p| ≤ C * harmonicTargetNorm hX p r w := by
    …

    Mentions: OAI.RegularPointCoordinates.NoncollapsedRCD, OAI.RegularPointCoordinates.LocalHarmonicL2MeanValueInput, OAI.RegularPointCoordinates.SobolevSpace, OAI.RegularPointCoordinates.hausdorff, OAI.RegularPointCoordinates.IsSobolevHarmonicOn, OAI.RegularPointCoordinates.SobolevSpace.toLp, OAI.RegularPointCoordinates.harmonicTargetNorm