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LeanPool.CaffarelliKohnNirenberg.Core.Endgame.TheoremBCloser

The gradient regularity criterion from a small-cell majorant #

For thm:B, suitable-solution slice derivatives determine one measurable pressure gradient. The slice majorant in sec:pressure transfers to this field by uniqueness. Finite covering supplies its whole-carrier integral, and the two cell regimes give the pressure-gradient input of the criterion.

Suitability supplies one measurable weak pressure gradient on a larger spatial carrier throughout the symmetric time window of thm:B.

theorem CKN.Core.Endgame.theoremB_gradient_producer_of_small_cell_majorant (hGaugeCorrectedSmallCellMajorant : ∀ (q τ : ℝ), 5 / 2 < q → 25 / 3 ≤ τ → τ ≤ 25 → ∀ {Ω : Set Foundation.Parabolic.Vec3} {I : Set ℝ} {u : Foundation.Parabolic.ParabolicPoint → Foundation.Parabolic.Vec3} {Du : Foundation.Parabolic.ParabolicPoint → Fin 3 → Foundation.Parabolic.Vec3} {p : Foundation.Parabolic.ParabolicPoint → ℝ} {f : Foundation.Parabolic.ParabolicPoint → Foundation.Parabolic.Vec3}, IsSuitableWeakSolutionIntegrable Ω I q u Du p f → ∀ (z₀ : Foundation.Parabolic.ParabolicPoint) (R : ℝ), 0 < R → Metric.ball z₀ (2 * R) ⊆ spaceTimeSet Ω I → morreyVecMem 3 τ (Metric.ball z₀ R) u → (∀ (i : Fin 3), morreyVecMem 2 (25 / 8) (Metric.ball z₀ R) fun (z : Foundation.Parabolic.ParabolicPoint) => Du z i) → ∃ (A : ENNReal) (N : Fin 3 → Foundation.Parabolic.Vec3 → ℝ → ℝ → ℝ → ENNReal), A < ⊤ ∧ (∀ (i : Fin 3) (c : Foundation.Parabolic.Vec3) (t ρ : ℝ), 0 < ρ → closure (Foundation.Parabolic.parabolicCylinder c t ρ) ⊆ spaceTimeSet Ω I → ∀ᵐ (s : ℝ) ∂MeasureTheory.volume.restrict (Set.Ioc (t - ρ ^ 2) t), ∃ (g : Foundation.Parabolic.Vec3 → ℝ), MeasureTheory.LocallyIntegrableOn g (euclideanBall c (ρ / 2)) MeasureTheory.volume ∧ HasWeakPartialDerivOn (euclideanBall c (ρ / 2)) i (fun (y : Vec 3) => p (y, s)) g ∧ MeasureTheory.eLpNorm g (ENNReal.ofReal (6 / 5)) (MeasureTheory.volume.restrict (euclideanBall c (ρ / 2))) ≤ N i c t ρ s) ∧ ∀ (i : Fin 3) (z : Foundation.Parabolic.ParabolicPoint) (r : ℝ), 0 < r → r ≤ R / 16 → (Foundation.Parabolic.parabolicCylinder z.1 z.2 r ∩ Metric.ball z₀ (R / 2)).Nonempty → ∫⁻ (s : ℝ) in Set.Ioc (z.2 - r ^ 2) z.2, N i z.1 z.2 (2 * r) s ^ (6 / 5) ≤ A * ENNReal.ofReal (r ^ (5 * (1 - 6 / 5 / min (1 / τ + 8 / 25)⁻¹ q)))) :

A finite small-cell slice majorant supplies the full pressure-gradient input of thm:B; the carrier integral follows by finite covering.

theorem CKN.Core.Endgame.epsilonRegularityGradient_closer_of_small_cell_majorant (q : ℝ) (hq : 5 / 2 < q) (hGaugeCorrectedSmallCellMajorant : ∀ (q τ : ℝ), 5 / 2 < q → 25 / 3 ≤ τ → τ ≤ 25 → ∀ {Ω : Set Foundation.Parabolic.Vec3} {I : Set ℝ} {u : Foundation.Parabolic.ParabolicPoint → Foundation.Parabolic.Vec3} {Du : Foundation.Parabolic.ParabolicPoint → Fin 3 → Foundation.Parabolic.Vec3} {p : Foundation.Parabolic.ParabolicPoint → ℝ} {f : Foundation.Parabolic.ParabolicPoint → Foundation.Parabolic.Vec3}, IsSuitableWeakSolutionIntegrable Ω I q u Du p f → ∀ (z₀ : Foundation.Parabolic.ParabolicPoint) (R : ℝ), 0 < R → Metric.ball z₀ (2 * R) ⊆ spaceTimeSet Ω I → morreyVecMem 3 τ (Metric.ball z₀ R) u → (∀ (i : Fin 3), morreyVecMem 2 (25 / 8) (Metric.ball z₀ R) fun (z : Foundation.Parabolic.ParabolicPoint) => Du z i) → ∃ (A : ENNReal) (N : Fin 3 → Foundation.Parabolic.Vec3 → ℝ → ℝ → ℝ → ENNReal), A < ⊤ ∧ (∀ (i : Fin 3) (c : Foundation.Parabolic.Vec3) (t ρ : ℝ), 0 < ρ → closure (Foundation.Parabolic.parabolicCylinder c t ρ) ⊆ spaceTimeSet Ω I → ∀ᵐ (s : ℝ) ∂MeasureTheory.volume.restrict (Set.Ioc (t - ρ ^ 2) t), ∃ (g : Foundation.Parabolic.Vec3 → ℝ), MeasureTheory.LocallyIntegrableOn g (euclideanBall c (ρ / 2)) MeasureTheory.volume ∧ HasWeakPartialDerivOn (euclideanBall c (ρ / 2)) i (fun (y : Vec 3) => p (y, s)) g ∧ MeasureTheory.eLpNorm g (ENNReal.ofReal (6 / 5)) (MeasureTheory.volume.restrict (euclideanBall c (ρ / 2))) ≤ N i c t ρ s) ∧ ∀ (i : Fin 3) (z : Foundation.Parabolic.ParabolicPoint) (r : ℝ), 0 < r → r ≤ R / 16 → (Foundation.Parabolic.parabolicCylinder z.1 z.2 r ∩ Metric.ball z₀ (R / 2)).Nonempty → ∫⁻ (s : ℝ) in Set.Ioc (z.2 - r ^ 2) z.2, N i z.1 z.2 (2 * r) s ^ (6 / 5) ≤ A * ENNReal.ofReal (r ^ (5 * (1 - 6 / 5 / min (1 / τ + 8 / 25)⁻¹ q)))) :

The gradient criterion thm:B, conditional only on the finite small-cell majorant for the pressure-gradient slices in sec:pressure.