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Project-declaredLean 4.29.0-rc6 · mathlib@5c8398df5281

Moser power Cutoff mem W01p energy of subsolution

DeGiorgi.moser_powerCutoff_memW01p_energy_of_subsolution

Plain-language statement

Analytic core of the Moser pre-estimate: the cutoff-power η · (u_+)^(p/2) belongs to W₀^{1,2} on the outer ball and satisfies the exact energy bound needed for Sobolev. The only remaining nonlinear gap is the construction of the underlying W^{1,2} witness and its energy bound.

Exact Lean statement

theorem moser_powerCutoff_memW01p_energy_of_subsolution
    (hd : 2 < (d : ℝ))
    (A : NormalizedEllipticCoeff d (Metric.ball (0 : E) 1))
    {u η : E → ℝ} {p s Cη : ℝ}
    (hp : 1 < p)
    (hs : 0 < s) (hs1 : s ≤ 1)
    (hsub : IsSubsolution A.1 u)
    (hpInt :
      IntegrableOn (fun x => |max (u x) 0| ^ p)
        (Metric.ball (0 : E) s) volume)
    (hη : ContDiff ℝ (⊤ : ℕ∞) η)
    (hη_nonneg : ∀ x, 0 ≤ η x)
    (hη_bound : ∀ x, |η x| ≤ 1)
    (hη_grad_bound : ∀ x, ‖fderiv ℝ η x‖ ≤ Cη)
    (hη_sub_ball : tsupport η ⊆ Metric.ball (0 : E) s) :
    ∃ hwv : MemW1pWitness 2 (moserPowerCutoff (d := d) η u p) (Metric.ball (0 : E) s),
      MemW01p 2 (moserPowerCutoff (d := d) η u p) (Metric.ball (0 : E) s) ∧
      ∫ x in Metric.ball (0 : E) s, ‖hwv.weakGrad x‖ ^ 2 ∂volume ≤
        2 * Cη ^ 2 * (A.1.Λ * (p / (p - 1)) ^ 2 + 1) *
          ∫ x in Metric.ball (0 : E) s, |max (u x) 0| ^ p ∂volume

Formal artifact

Lean source

Canonical source
Full Lean sourceLean 4
theorem moser_powerCutoff_memW01p_energy_of_subsolution    (hd : 2 < (d : ))    (A : NormalizedEllipticCoeff d (Metric.ball (0 : E) 1))    {u η : E  } {p s Cη : }    (hp : 1 < p)    (hs : 0 < s) (hs1 : s  1)    (hsub : IsSubsolution A.1 u)    (hpInt :      IntegrableOn (fun x => |max (u x) 0| ^ p)        (Metric.ball (0 : E) s) volume)    (hη : ContDiff  (⊤ : ∞) η)    (hη_nonneg :  x, 0  η x)    (hη_bound :  x, |η x|  1)    (hη_grad_bound :  x, ‖fderiv  η x‖  Cη)    (hη_sub_ball : tsupport η  Metric.ball (0 : E) s) :     hwv : MemW1pWitness 2 (moserPowerCutoff (d := d) η u p) (Metric.ball (0 : E) s),      MemW01p 2 (moserPowerCutoff (d := d) η u p) (Metric.ball (0 : E) s)       ∫ x in Metric.ball (0 : E) s, ‖hwv.weakGrad x‖ ^ 2 ∂volume         2 *^ 2 * (A.1* (p / (p - 1)) ^ 2 + 1) *          ∫ x in Metric.ball (0 : E) s, |max (u x) 0| ^ p ∂volume := by  let Ω : Set E := Metric.ball (0 : E) s  let v : E   := moserPowerCutoff (d := d) η u p  have hv_support : tsupport v  Ω :=    moserPowerCutoff_tsupport_subset (d := d) (u := u) (η := η) (p := p) hη_sub_ball  obtain hwv, henergy :=    moser_powerCutoff_memW1p_energy_of_subsolution_core      (d := d) hd A (u := u) (η := η) (p := p) (s := s) (Cη := Cη)      hp hs hs1 hsub hpInt hη hη_nonneg hη_bound hη_grad_bound hη_sub_ball  have hv_compact : HasCompactSupport v :=    hasCompactSupport_of_tsupport_subset_ball hv_support  have hv_memW1p_real : MemW1p (ENNReal.ofReal (2 : )) v Ω := by    simpa [Ω] using hwv.memW1p  have hvW01_real : MemW01p (ENNReal.ofReal (2 : )) v Ω := by    exact memW01p_of_memW1p_of_tsupport_subset      (d := d) Metric.isOpen_ball (p := (2 : )) (by norm_num) hv_memW1p_real hv_compact hv_support  have hvW01 : MemW01p 2 v Ω := by    simpa [Ω] using hvW01_real  exact hwv, hvW01, henergy
Project
DeGiorgi
License
Apache-2.0
Commit
4c1b3077d378
Source
DeGiorgi/MoserIteration/CutoffPrep/PreEstimate.lean:49-86

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