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Project-declaredLean 4.29.0-rc6 · mathlib@5c8398df5281

De Giorgi Cutoff Test mem W01p of pos Part

DeGiorgi.deGiorgiCutoffTest_memW01p_of_posPart

Project documentation

General cutoff admissibility theorem, parameterized by a positive-part witness theorem. This packages the reusable cutoff argument while keeping the localization argument in memW01p_of_memW1p_of_tsupport_subset.

Exact Lean statement

theorem deGiorgiCutoffTest_memW01p_of_posPart
    {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)
    (hpos :
      ∀ {v : E → ℝ},
        MemW1pWitness 2 v Ω →
          MemW1pWitness 2 (fun x => max (v x) 0) Ω) :
    MemW01p 2 (deGiorgiCutoffTestGeneral η u k) Ω

Formal artifact

Lean source

Canonical source
Full Lean sourceLean 4
theorem deGiorgiCutoffTest_memW01p_of_posPart    {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 : )    (hpos :       {v : E  },        MemW1pWitness 2 v Ω           MemW1pWitness 2 (fun x => max (v x) 0) Ω) :    MemW01p 2 (deGiorgiCutoffTestGeneral η u k) Ω := by  let hwShift : MemW1pWitness 2 (fun x => u x - k) Ω := hw.sub_const hΩ k  have hw_trunc : MemW1pWitness 2 (positivePartSub u k) Ω := by    simpa [positivePartSub] using (hpos hwShift)  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:137-160

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