OAI/Geometry/RCD/Sobolev/GoodLaplacianCutoff.lean

GitHub source file

5 declarations, 0 contain sorry, 0 declared as axioms

Quantitative cutoff input and its canonical Bochner application

The existence input is the fixed radius-ratio specialization of Mondino-- Naber (2019), Lemma 3.1 (arXiv:1405.2222v3, pp.13--14), also stated in Connell et al. (2021), Lemma 2.6. Scaling to unit radius and lowering the curvature bound to -1 makes its constant dimensional. Support of the Laplacian off the transition region is the locality of the weak Laplacian.

  1. structure OAI.RegularPointCoordinates.GoodLaplacianCutoff line 26

    Source documentation

    An actual Sobolev cutoff with bounded weak Laplacian.

    structure GoodLaplacianCutoff (p : X) (r C : ℝ) where
    …
  2. def OAI.RegularPointCoordinates.LocalGoodCutoffInput line 41

    Source documentation

    Exact existence consequence at bounded rescaled curvature.

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

    Mentions: OAI.RegularPointCoordinates.NoncollapsedRCD

  3. theorem OAI.RegularPointCoordinates.GoodLaplacianCutoff.tsupport_subset line 49

    Source documentation

    The topological support remains inside the closed outer ball.

    theorem tsupport_subset {p : X} {r C : ℝ} (χ : GoodLaplacianCutoff μ hQ p r C) :
        tsupport (χ.weight : X → ℝ) ⊆ closedBall p (2 * r) := by
    …

    Mentions: OAI.RegularPointCoordinates.GoodLaplacianCutoff

  4. theorem OAI.RegularPointCoordinates.GoodLaplacianCutoff.hasCompactSupport line 57
  5. theorem OAI.RegularPointCoordinates.GoodLaplacianCutoff.harmonic_mass_le line 63

    Source documentation

    The good cutoff and local harmonic Bochner equation imply small mass on the inner ball, without a separate raw-source assumption.

    theorem harmonic_mass_le [IsFiniteMeasureOnCompacts μ]
        {n : ℕ} {p : X} {ρ C r κ : ℝ} {L : ℝ≥0}
        (χ : GoodLaplacianCutoff μ hQ p ρ C) (hρ : 0 < ρ) (hρr : ρ < r)
        (hC : 0 ≤ C) (hκ : 0 ≤ κ) (u : Fin n → SobolevSpace μ hQ)
        (M : PositiveBilinearMeasure X (Euclidean n))
        (G : ∀ v, LocalHarmonicEnergy μ hQ (sobolevColumnMap μ hQ u) M κ p r L v)
        {ε : ℝ} (hε : 0 ≤ ε)
        (herror : ∀ i j : Fin n, ∫ x in closedBall p (2 * ρ),
          |localGamma μ hQ (u i) (u j) x - (if i = j then 1 else 0)| ∂μ ≤ ε)
        (v : Euclidean n) :
        ⟪v, M.massOperator (ball p ρ) v⟫_ℝ ≤
          ((C / ρ ^ 2) * ((n : ℝ) ^ 2 * ε) / 2 +
    …

    Mentions: OAI.RegularPointCoordinates.GoodLaplacianCutoff, OAI.RegularPointCoordinates.SobolevSpace, OAI.RegularPointCoordinates.PositiveBilinearMeasure, OAI.RegularPointCoordinates.Euclidean, OAI.RegularPointCoordinates.LocalHarmonicEnergy, OAI.RegularPointCoordinates.sobolevColumnMap, OAI.RegularPointCoordinates.localGamma