OAI/Geometry/RCD/Sobolev/PoissonHeight.lean

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2 declarations, 0 contain sorry, 0 declared as axioms

Height control for the Poisson replacement

A bounded torsion solution and the weak boundary maximum principle provide the bound needed by the positive-source gradient estimate.

  1. theorem OAI.RegularPointCoordinates.exists_uniform_bounded_torsion line 26

    Source documentation

    Coercivity constructs torsion and the Sobolev iteration bounds it with a constant uniform over all the displayed domains.

    theorem exists_uniform_bounded_torsion {d C V : ℝ} (hd : 1 < d)
        (hC : 0 ≤ C) (hV : 0 ≤ V) :
        ∃ K : ℝ, 0 < K ∧ ∀ (Ω : Set X), MeasurableSet Ω → μ Ω ≠ ∞ → μ.real Ω ≤ V →
          ∀ P : ℝ, 0 ≤ P →
          (∀ v : SobolevSpace.dirichlet μ hQ Ω,
            ‖SobolevSpace.toLp μ hQ v.val‖ ^ 2 ≤ P * energyForm μ hQ v.val v.val) →
          (∀ φ : SobolevSpace.dirichlet μ hQ Ω,
            (∫ x in Ω, |SobolevSpace.toLp μ hQ φ.val x| ^ (2 * d) ∂μ) ^ (1 / d) ≤
              C * energyForm μ hQ φ.val φ.val) →
          ∃ τ : SobolevSpace.dirichlet μ hQ Ω,
            (∀ φ : SobolevSpace.dirichlet μ hQ Ω,
              energyForm μ hQ τ.val φ.val = ∫ x in Ω, SobolevSpace.toLp μ hQ φ.val x ∂μ) ∧
    …

    Mentions: OAI.RegularPointCoordinates.SobolevSpace.dirichlet, OAI.RegularPointCoordinates.SobolevSpace.toLp, OAI.RegularPointCoordinates.energyForm

  2. theorem OAI.RegularPointCoordinates.poisson_replacement_height_le line 64

    Source documentation

    Torsion comparison bounds the nonnegative difference of the boundary datum and its constant-Laplacian replacement.

    theorem poisson_replacement_height_le (Ω : Set X) (hΩ : MeasurableSet Ω)
        (hfin : μ Ω ≠ ∞) {P : ℝ} (hP : 0 ≤ P)
        (hpoin : ∀ v : SobolevSpace.dirichlet μ hQ Ω,
          ‖SobolevSpace.toLp μ hQ v.val‖ ^ 2 ≤ P * energyForm μ hQ v.val v.val)
        (q f : SobolevSpace μ hQ) (Q : X → ℝ) {L : ℝ≥0}
        (hQlip : LipschitzWith L Q) (hQ0 : ∀ x, 0 ≤ Q x)
        (hq : SobolevSpace.toLp μ hQ q =ᵐ[μ] Q)
        {a B K : ℝ} (ha : 0 ≤ a) (hB : 0 ≤ B) (hK : 0 ≤ K)
        (hQB : ∀ᵐ x ∂μ.restrict Ω, Q x ≤ B)
        (τ : SobolevSpace.dirichlet μ hQ Ω)
        (hτ : ∀ φ : SobolevSpace.dirichlet μ hQ Ω,
          energyForm μ hQ τ.val φ.val = ∫ x in Ω, SobolevSpace.toLp μ hQ φ.val x ∂μ)
    …

    Mentions: OAI.RegularPointCoordinates.SobolevSpace.dirichlet, OAI.RegularPointCoordinates.SobolevSpace.toLp, OAI.RegularPointCoordinates.energyForm, OAI.RegularPointCoordinates.SobolevSpace