OAI/Geometry/RCD/Sobolev/LocalHolderMoment.lean

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2 declarations, 0 contain sorry, 0 declared as axioms

The localized Hölder step for harmonic level sets

  1. theorem OAI.RegularPointCoordinates.square_integral_le_higher_moment line 17

    Source documentation

    On a finite measure space, a superquadratic moment controls L² with the exact measure power used in the level-set iteration.

    theorem square_integral_le_higher_moment [IsFiniteMeasure μ]
        {f : X → ℝ} (hf : AEStronglyMeasurable f μ) {p : ℝ} (hp : 2 < p)
        (hi : Integrable (fun x => |f x|^p) μ) :
        (∫ x, (f x)^2 ∂μ) ≤ (∫ x, |f x|^p ∂μ)^(2/p)*
          (μ.real univ)^(1-2/p) := by
    …
  2. theorem OAI.RegularPointCoordinates.square_setIntegral_le_higher_moment line 51

    Source documentation

    Restricting the L² integral to a level set inserts a positive power of its measure while retaining the moment on the outer domain.

    theorem square_setIntegral_le_higher_moment {Ω A : Set X}
        (_hΩ : MeasurableSet Ω) (_hA : MeasurableSet A) (hAΩ : A ⊆ Ω)
        (hfin : μ Ω < ∞) {f : X → ℝ} (hf : AEStronglyMeasurable f (μ.restrict Ω))
        {p : ℝ} (hp : 2 < p) (hi : IntegrableOn (fun x => |f x|^p) Ω μ) :
        (∫ x in A, (f x)^2 ∂μ) ≤ (∫ x in Ω, |f x|^p ∂μ)^(2/p)*
          (μ.real A)^(1-2/p) := by
    …