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))) * IθFormal artifact
Lean source
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 := 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 * Iθ := by calc μ.real {x | lam < u x} ≤ ((lam - θ) ^ 2)⁻¹ * ∫ x, |positivePartSub u θ x| ^ 2 ∂μ := hmeasure0 _ ≤ ((lam - θ) ^ 2)⁻¹ * Iθ := 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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Source project: DeGiorgi
Person-level attribution pending.
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Source project: DeGiorgi
Person-level attribution pending.