OAI/Geometry/RCD/Sobolev/AveragedCutoffError.lean

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3 declarations, 0 contain sorry, 0 declared as axioms

Exact quadratic identities for the averaged cutoff error

  1. theorem OAI.RegularPointCoordinates.GoodLaplacianCutoff.error_zero_off_outerBall line 19

    Source documentation

    The actual product-rule source is supported in the closed outer ball.

    theorem GoodLaplacianCutoff.error_zero_off_outerBall {p : X} {ρ C : ℝ}
        (χ : GoodLaplacianCutoff μ hQ p ρ C) (u : SobolevSpace μ hQ) :
        ∀ᵐ z ∂μ, z ∉ closedBall p (2 * ρ) →
          cutoffSourceDensity μ hQ u χ.sobolev χ.laplacian z = 0 := by
    …

    Mentions: OAI.RegularPointCoordinates.GoodLaplacianCutoff, OAI.RegularPointCoordinates.SobolevSpace, OAI.RegularPointCoordinates.cutoffSourceDensity

  2. theorem OAI.RegularPointCoordinates.averaged_cutoff_error_energy line 38

    Source documentation

    The averaged error is quadratic in every direction; this follows from the actual pointwise heat equation and Fubini, not an extra quadraticity input.

    theorem averaged_cutoff_error_energy (hρ : 0 < ρ) (hρr : ρ < r)
        {t : ℝ} (ht : 0 < t) (A : Set X) (hA : MeasurableSet A)
        (hbounded : Bornology.IsBounded A) (v : Euclidean n) :
        ⟪v, polarizedDerivative (fun w => ∫ z, kernelAverage μ ker t A z *
          cutoffSourceDensity μ hQ (G w).energy χ.sobolev χ.laplacian z ∂μ) v⟫_ℝ =
          ∫ z, kernelAverage μ ker t A z *
            cutoffSourceDensity μ hQ (G v).energy χ.sobolev χ.laplacian z ∂μ := by
    …

    Mentions: OAI.RegularPointCoordinates.Euclidean, OAI.RegularPointCoordinates.polarizedDerivative, OAI.RegularPointCoordinates.kernelAverage, OAI.RegularPointCoordinates.cutoffSourceDensity

  3. theorem OAI.RegularPointCoordinates.difference_cutoff_error_energy line 72

    Source documentation

    The averaged-minus-pointwise source pairing is likewise the quadratic form of its finite polarization.

    theorem difference_cutoff_error_energy (hρ : 0 < ρ) (hρr : ρ < r)
        {t : ℝ} (ht : 0 < t) (A : Set X) (hA : MeasurableSet A)
        (hbounded : Bornology.IsBounded A) (x : X) (v : Euclidean n) :
        ⟪v, polarizedDerivative (fun w => ∫ z, (kernelAverage μ ker t A z - ker t x z) *
          cutoffSourceDensity μ hQ (G w).energy χ.sobolev χ.laplacian z ∂μ) v⟫_ℝ =
          ∫ z, (kernelAverage μ ker t A z - ker t x z) *
            cutoffSourceDensity μ hQ (G v).energy χ.sobolev χ.laplacian z ∂μ := by
    …

    Mentions: OAI.RegularPointCoordinates.Euclidean, OAI.RegularPointCoordinates.polarizedDerivative, OAI.RegularPointCoordinates.kernelAverage, OAI.RegularPointCoordinates.cutoffSourceDensity