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Project-declaredLean 4.29.0-rc6 · mathlib@5c8398df5281

De Giorgi Cutoff Test mem W01p of pos Part Approx

DeGiorgi.deGiorgiCutoffTest_memW01p_of_posPartApprox

Project documentation

Concrete cutoff admissibility theorem using the Chapter 02 positive-part witness constructor and an explicit smooth-approximation package for u - k.

Exact Lean statement

theorem deGiorgiCutoffTest_memW01p_of_posPartApprox
    {Ω : Set E} [IsFiniteMeasure (volume.restrict Ω)]
    (hΩ : IsOpen Ω)
    {u η : E → ℝ}
    (hw : MemW1pWitness 2 u Ω)
    (hη : ContDiff ℝ (⊤ : ℕ∞) η)
    {C₀ C₁ : ℝ}
    (hC₀ : 0 ≤ C₀) (hC₁ : 0 ≤ C₁)
    (hη_bound : ∀ x, |η x| ≤ C₀)
    (hη_grad_bound : ∀ x, ‖fderiv ℝ η x‖ ≤ C₁)
    (hη_comp : HasCompactSupport η)
    (hη_sub : tsupport η ⊆ Ω)
    (k : ℝ)
    (happroxShift :
      ∃ ψ : ℕ → E → ℝ,
        (∀ n, ContDiff ℝ 1 (ψ n)) ∧
        (∀ n, HasCompactSupport (ψ n)) ∧
        Tendsto (fun n => eLpNorm (fun x => ψ n x - (u x - k)) 2 (volume.restrict Ω))
          atTop (nhds 0) ∧
        (∀ i : Fin d,
          Tendsto (fun n => eLpNorm (fun x =>
            (fderiv ℝ (ψ n) x) (EuclideanSpace.single i 1) - hw.weakGrad x i)
            2 (volume.restrict Ω))
          atTop (nhds 0))) :
    MemW01p 2 (deGiorgiCutoffTestGeneral η u k) Ω

Formal artifact

Lean source

Canonical source
Full Lean sourceLean 4
theorem deGiorgiCutoffTest_memW01p_of_posPartApprox    {Ω : Set E} [IsFiniteMeasure (volume.restrict Ω)]    (hΩ : IsOpen Ω)    {u η : E  }    (hw : MemW1pWitness 2 u Ω)    (hη : ContDiff  (⊤ : ∞) η)    {C₀ C₁ : }    (hC₀ : 0  C₀) (hC₁ : 0  C₁)    (hη_bound :  x, |η x|  C₀)    (hη_grad_bound :  x, ‖fderiv  η x‖  C₁)    (hη_comp : HasCompactSupport η)    (hη_sub : tsupport η  Ω)    (k : )    (happroxShift :       ψ :   E  ,        ( n, ContDiff  1 (ψ n))         ( n, HasCompactSupport (ψ n))         Tendsto (fun n => eLpNorm (fun x => ψ n x - (u x - k)) 2 (volume.restrict Ω))          atTop (nhds 0)         ( i : Fin d,          Tendsto (fun n => eLpNorm (fun x =>            (fderiv  (ψ n) x) (EuclideanSpace.single i 1) - hw.weakGrad x i)            2 (volume.restrict Ω))          atTop (nhds 0))) :    MemW01p 2 (deGiorgiCutoffTestGeneral η u k) Ω := by  let hw_trunc : MemW1pWitness 2 (positivePartSub u k) Ω :=    positivePartSub_memW1pWitness hΩ hw k happroxShift  exact    deGiorgiCutoffTest_memW01p_of_truncWitness      hΩ hw_trunc hη hC₀ hC₁ hη_bound hη_grad_bound hη_comp hη_sub
Project
DeGiorgi
License
Apache-2.0
Commit
4c1b3077d378
Source
DeGiorgi/DeGiorgiIteration/CutoffAdmissibility.lean:164-193

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