Compactness Pairing Continuity #
Supporting estimates for the Navier–Stokes development.
theorem
CKN.Leray.continuous_compactnessMollifiedLimit_local_pairing
{U : Set Foundation.Parabolic.Vec3}
{I : Set ℝ}
(u : ℕ → Foundation.Parabolic.Vec3 × ℝ → Foundation.Parabolic.Vec3)
(σ : ℕ → ℕ)
(K : ℕ → Set Foundation.Parabolic.Vec3)
(χ : ℕ → Foundation.Parabolic.Vec3 → ℝ)
(hK : ∀ (j : ℕ), IsCompact (K j) ∧ K j ⊆ U ∧ K j ⊆ K (j + 1) ∧ K j ⊆ interior (K (j + 1)))
(hKcover : ⋃ (j : ℕ), K j = U)
(hχ : ∀ (j : ℕ), ∀ x ∈ K j, χ j x = 1)
(hmem :
∀ (n j : ℕ) (t : ↑I),
MeasureTheory.MemLp (fun (x : Foundation.Parabolic.Vec3) => χ j x • WithLp.toLp 2 (u n (x, ↑t))) 2
MeasureTheory.volume)
(V : ℕ → ↑I → ↥(MeasureTheory.Lp Foundation.Parabolic.L2Vec3 2 MeasureTheory.volume))
(hweak :
∀ (j : ℕ) (t : ↑I) (x : ↥(MeasureTheory.Lp (WithLp 2 Foundation.Parabolic.Vec3) 2 MeasureTheory.volume)),
Filter.Tendsto
(fun (k : ℕ) =>
inner ℝ
(MeasureTheory.MemLp.toLp (fun (y : Foundation.Parabolic.Vec3) => χ j y • WithLp.toLp 2 (u (σ k) (y, ↑t))) ⋯)
x)
Filter.atTop (nhds (inner ℝ (V j t) x)))
(hVcont :
∀ (j : ℕ) (x : ↥(MeasureTheory.Lp Foundation.Parabolic.L2Vec3 2 MeasureTheory.volume)),
Continuous fun (t : ↑I) => inner ℝ (V j t) x)
(C : Set Foundation.Parabolic.Vec3)
(hC : IsCompact C)
(hCU : C ⊆ U)
(w : ↥(MeasureTheory.Lp Foundation.Parabolic.L2Vec3 2 (MeasureTheory.volume.restrict C)))
:
Continuous fun (t : ↑I) =>
∫ (x : Foundation.Parabolic.Vec3) in C, ∑ i : Fin 3, compactnessMollifiedLimit u σ (x, ↑t) i * (↑↑w x).ofLp i
Pairing the selected representative against a fixed local L² test is continuous in time.