The compactness limit is a strong solution #
The compactness limit of the regularized solutions, with the continuous representative of its
gradient and the pressure of the Leray--Hopf limit, is a strong solution on the closed time interval
(prop:lps-local-strong).
theorem
ESS.LPS.lps_strong_limit_solution
(ρ : CKN.Leray.RegMollifierProfile)
(b : CKN.Foundation.Parabolic.Vec3 → CKN.Foundation.Parabolic.Vec3)
(Db : CKN.Foundation.Parabolic.Vec3 → Fin 3 → CKN.Foundation.Parabolic.Vec3)
(hb :
IsLpsGoodTime (fun (z : CKN.Foundation.Parabolic.ParabolicPoint) => b z.1)
(fun (z : CKN.Foundation.Parabolic.ParabolicPoint) (i : Fin 3) => Db z.1 i) 0)
(T M : ℝ)
(hT : 0 < T)
(hclause :
∀ (ε : ℝ) (hε : 0 < ε),
have Uε := CKN.Leray.regR12Velocity ρ ε hε b ⋯;
have Dε := fun (z : CKN.Foundation.Parabolic.ParabolicPoint) (i j : Fin 3) =>
CKN.spatialPartial (fun (y : CKN.Foundation.Parabolic.ParabolicPoint) => Uε y i) j z;
have D2ε := fun (z : CKN.Foundation.Parabolic.ParabolicPoint) (i j k : Fin 3) =>
CKN.spatialPartial
(fun (y : CKN.Foundation.Parabolic.ParabolicPoint) =>
CKN.spatialPartial (fun (x : CKN.Foundation.Parabolic.ParabolicPoint) => Uε x i) j y)
k z;
(∀ t ∈ Set.Icc 0 T,
∫ (x : CKN.Foundation.Parabolic.Vec3), CKN.Foundation.Parabolic.vec3EuclideanNorm (Uε (x, t)) ^ 2 + CKN.spatialGradientSq Uε Dε (x, t) ≤ M) ∧ ∫ (z : CKN.Foundation.Parabolic.ParabolicPoint) in CKN.spaceTimeSet Set.univ (Set.Ioo 0 T), ∑ i : Fin 3, ∑ j : Fin 3, CKN.Foundation.Parabolic.vec3EuclideanNorm (D2ε z i j) ^ 2 ≤ M)
:
∃ (u : CKN.Foundation.Parabolic.ParabolicPoint → CKN.Foundation.Parabolic.Vec3) (Du :
CKN.Foundation.Parabolic.ParabolicPoint → Fin 3 → CKN.Foundation.Parabolic.Vec3) (p :
CKN.Foundation.Parabolic.ParabolicPoint → ℝ),
IsLpsStrongSolution 0 T u Du p ∧ (fun (x : CKN.Foundation.Parabolic.Vec3) => u (x, 0)) =ᵐ[MeasureTheory.volume] b
The limit of the regularized solutions with uniform H¹ and L²_tH² bounds is a strong
solution on [0, T] with the good initial datum as trace (prop:lps-local-strong).