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Project-declaredLean 4.29.0-rc6 · mathlib@5c8398df5281

De Giorgi preiter of energy

DeGiorgi.deGiorgi_preiter_of_energy

Plain-language statement

Packaged pre-iteration step after Sobolev, energy, and Chebyshev inputs.

Exact Lean statement

theorem deGiorgi_preiter_of_energy
    {α : Type*} [MeasurableSpace α] {μ : Measure α} [IsFiniteMeasure μ]
    {d : ℕ} (hd : 0 < (d : ℝ))
    {u : α → ℝ} {θ lam : ℝ}
    {Ilam Iθ G Csob Cenergy : ℝ}
    (hθl : θ < lam)
    (hCsob : 0 ≤ Csob) (hCenergy : 0 ≤ Cenergy)
    (hIθ : 0 ≤ Iθ)
    (hint : Integrable (fun x => |positivePartSub u θ x| ^ 2) μ)
    (hsob :
      Ilam ≤ Csob * G * (μ.real {x | lam < u x}) ^ (2 / (d : ℝ)))
    (henergy :
      G ≤ Cenergy * Iθ)
    (hIθ_bound :
      ∫ x, |positivePartSub u θ x| ^ 2 ∂μ ≤ Iθ) :
    Ilam ≤
      Csob * Cenergy * ((((lam - θ) ^ 2)⁻¹ * Iθ) ^ (2 / (d : ℝ))) * Iθ

Formal artifact

Lean source

Canonical source
Full Lean sourceLean 4
theorem deGiorgi_preiter_of_energy    {α : Type*} [MeasurableSpace α] {μ : Measure α} [IsFiniteMeasure μ]    {d : } (hd : 0 < (d : ))    {u : α  } {θ lam : }    {Ilam Iθ G Csob Cenergy : }    (hθl : θ < lam)    (hCsob : 0  Csob) (hCenergy : 0  Cenergy)    (hIθ : 0  Iθ)    (hint : Integrable (fun x => |positivePartSub u θ x| ^ 2) μ)    (hsob :      Ilam  Csob * G * (μ.real {x | lam < u x}) ^ (2 / (d : )))    (henergy :      G  Cenergy * Iθ)    (hIθ_bound :      ∫ x, |positivePartSub u θ x| ^ 2 ∂μ  Iθ) :    Ilam       Csob * Cenergy * ((((lam - θ) ^ 2)⁻¹ * Iθ) ^ (2 / (d : ))) *:= by  have hm_nonneg : 0  μ.real {x | lam < u x} := measureReal_nonneg  have hmeasure0 :      μ.real {x | lam < u x}         ((lam - θ) ^ 2)⁻¹ * ∫ x, |positivePartSub u θ x| ^ 2 ∂μ :=    superlevel_measureReal_le_integral_posPart hθl hint  have hmeasure :      μ.real {x | lam < u x}  ((lam - θ) ^ 2)⁻¹ *:= by    calc      μ.real {x | lam < u x}           ((lam - θ) ^ 2)⁻¹ * ∫ x, |positivePartSub u θ x| ^ 2 ∂μ := hmeasure0      _  ((lam - θ) ^ 2)⁻¹ *:= by        gcongr  exact deGiorgi_preiter_abstract hd hCsob hCenergy hIθ hm_nonneg hsob hmeasure henergy
Project
DeGiorgi
License
Apache-2.0
Commit
4c1b3077d378
Source
DeGiorgi/DeGiorgiIteration/Energy.lean:1108-1137

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Project-declaredLean 4.29.0-rc6

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Source project: DeGiorgi

Person-level attribution pending.

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