thm:leray by the direct route #
The regularized solutions of thm:regularised are the pointwise velocity of
the global regularized mild curve and its canonical Riesz pressure. With the
global Bessel lift of the curve, the pressure regularity, the classical time
derivative and joint continuous differentiability, they satisfy the full
contract (R1)–(R5). Together with lem:reg-tails and prop:leray-limit, the
direct limiting argument then gives thm:leray.
theorem
CKN.Leray.regR12_regularised_unconditional
(ρ : RegMollifierProfile)
(a : Foundation.Parabolic.Vec3 → Foundation.Parabolic.Vec3)
(ha : IsInJ a)
(ε : ℝ)
(hε : 0 < ε)
:
have u := regR12Uε ρ a ha ε;
have p := regR12Pε ρ a ha ε;
have D := fun (z : Foundation.Parabolic.ParabolicPoint) (i j : Fin 3) =>
spatialPartial (fun (y : Foundation.Parabolic.ParabolicPoint) => u y i) j z;
have DD := fun (z : Foundation.Parabolic.ParabolicPoint) (i j k : Fin 3) =>
spatialPartial
(fun (y : Foundation.Parabolic.ParabolicPoint) =>
spatialPartial (fun (x : Foundation.Parabolic.ParabolicPoint) => u x i) j y)
k z;
have Dt := fun (z : Foundation.Parabolic.ParabolicPoint) (i : Fin 3) =>
timePartial (fun (y : Foundation.Parabolic.ParabolicPoint) => u y i) z;
have Dp := fun (z : Foundation.Parabolic.ParabolicPoint) (i : Fin 3) =>
spatialPartial (fun (y : Foundation.Parabolic.ParabolicPoint) => p y) i z;
(∃ (hSlice :
∀ (t : ℝ), 0 ≤ t → MeasureTheory.MemLp (fun (x : Foundation.Parabolic.Vec3) => u (x, t)) 2 MeasureTheory.volume),
(Continuous fun (t : ↑(Set.Ici 0)) =>
realVectorL2OfCoordinateFunction (fun (x : Foundation.Parabolic.Vec3) => u (x, ↑t)) ⋯) ∧ (fun (x : Foundation.Parabolic.Vec3) => u (x, 0)) =ᵐ[MeasureTheory.volume] regUniformMollifiedInitial ρ ε hε a ∧ ∀ (t : ℝ), 0 ≤ t → IsWeakDivFreeL2 fun (x : Foundation.Parabolic.Vec3) => u (x, t)) ∧ (∀ (i : Fin 3),
ContinuousOn (fun (z : Foundation.Parabolic.ParabolicPoint) => u z i) (spaceTimeSet Set.univ (Set.Ioi 0))) ∧ (∀ (i j : Fin 3),
ContinuousOn (fun (z : Foundation.Parabolic.ParabolicPoint) => D z i j) (spaceTimeSet Set.univ (Set.Ioi 0))) ∧ (∀ (i j k : Fin 3),
ContinuousOn (fun (z : Foundation.Parabolic.ParabolicPoint) => DD z i j k)
(spaceTimeSet Set.univ (Set.Ioi 0))) ∧ (∀ (i : Fin 3),
ContinuousOn (fun (z : Foundation.Parabolic.ParabolicPoint) => Dt z i)
(spaceTimeSet Set.univ (Set.Ioi 0))) ∧ ContinuousOn p (spaceTimeSet Set.univ (Set.Ioi 0)) ∧ (∀ (i : Fin 3),
ContinuousOn (fun (z : Foundation.Parabolic.ParabolicPoint) => Dp z i)
(spaceTimeSet Set.univ (Set.Ioi 0))) ∧ (∀ (i : Fin 3),
ContDiffOn ℝ 1 (fun (z : Foundation.Parabolic.ParabolicPoint) => u z i)
(spaceTimeSet Set.univ (Set.Ioi 0))) ∧ (∀ z ∈ spaceTimeSet Set.univ (Set.Ioi 0),
∀ (i j : Fin 3), DifferentiableAt ℝ (fun (x : Foundation.Parabolic.Vec3) => D (x, z.2) i j) z.1) ∧ (∀ z ∈ spaceTimeSet Set.univ (Set.Ioi 0),
DifferentiableAt ℝ (fun (x : Foundation.Parabolic.Vec3) => p (x, z.2)) z.1) ∧ (∀ (δ T : ℝ),
0 < δ →
δ < T →
∃ (C : ℝ),
0 ≤ C ∧ ∀ z ∈ spaceTimeSet Set.univ (Set.Icc δ T),
Foundation.Parabolic.vec3EuclideanNorm (u z) ≤ C ∧ |p z| ≤ C ∧ (∀ (i j : Fin 3), |D z i j| ≤ C) ∧ (∀ (i j k : Fin 3), |DD z i j k| ≤ C) ∧ (∀ (i : Fin 3), |Dt z i| ≤ C) ∧ ∀ (i : Fin 3), |Dp z i| ≤ C) ∧ (∀ (δ T : ℝ),
0 < δ →
δ < T →
(∀ (i : Fin 3),
MeasureTheory.MemLp (fun (z : Foundation.Parabolic.ParabolicPoint) => u z i) 2
(MeasureTheory.volume.restrict (spaceTimeSet Set.univ (Set.Ioo δ T)))) ∧ (∀ (i j : Fin 3),
MeasureTheory.MemLp (fun (z : Foundation.Parabolic.ParabolicPoint) => D z i j) 2
(MeasureTheory.volume.restrict (spaceTimeSet Set.univ (Set.Ioo δ T)))) ∧ (∀ (i j k : Fin 3),
MeasureTheory.MemLp (fun (z : Foundation.Parabolic.ParabolicPoint) => DD z i j k)
2 (MeasureTheory.volume.restrict (spaceTimeSet Set.univ (Set.Ioo δ T)))) ∧ (∀ (i : Fin 3),
MeasureTheory.MemLp (fun (z : Foundation.Parabolic.ParabolicPoint) => Dt z i) 2
(MeasureTheory.volume.restrict (spaceTimeSet Set.univ (Set.Ioo δ T)))) ∧ MeasureTheory.MemLp p 2
(MeasureTheory.volume.restrict (spaceTimeSet Set.univ (Set.Ioo δ T)))) ∧ (∀ (z : Foundation.Parabolic.ParabolicPoint),
0 < z.2 →
∀ (i : Fin 3),
Dt z i - ∑ j : Fin 3, DD z i j j + ∑ j : Fin 3, regUniformMollifiedVelocity ρ ε hε u z j * D z i j + Dp z i = 0) ∧ (∀ (t : ℝ),
0 < t →
∃ (hF :
∀ (i j : Fin 3),
MeasureTheory.MemLp
(fun (x : Foundation.Parabolic.Vec3) =>
regUniformMollifiedVelocity ρ ε hε u (x, t) i * u (x, t) j)
(ENNReal.ofReal 2) MeasureTheory.volume),
((fun (x : Foundation.Parabolic.Vec3) => p (x, t)) =ᵐ[MeasureTheory.volume]
rieszPressureSliceRepresentative 2 regR12_regularised_unconditional._proof_55
fun (i j : Fin 3) =>
MeasureTheory.MemLp.toLp
(fun (x : Foundation.Parabolic.Vec3) =>
regUniformMollifiedVelocity ρ ε hε u (x, t) i * u (x, t) j)
⋯) ∧ ∀ (ψ : Foundation.Parabolic.Vec3 → ℝ),
ContDiff ℝ (↑⊤) ψ →
HasCompactSupport ψ →
∫ (x : Foundation.Parabolic.Vec3), p (x, t) * spatialLaplacian ψ x = -∑ i : Fin 3,
∑ j : Fin 3,
∫ (x : Foundation.Parabolic.Vec3), regUniformMollifiedVelocity ρ ε hε u (x, t) i * u (x, t) j * mixedSecond ψ i j x) ∧ ∀ (t : ℝ),
0 ≤ t →
MeasureTheory.eLpNorm (regUniformVelocitySlice u t) 2 MeasureTheory.volume ^ 2 + 2 * regUniformDissipation u D t = MeasureTheory.eLpNorm (regMollifyVector ρ ε hε (regUniformSpatialField a)) 2
MeasureTheory.volume ^ 2
thm:regularised, (R1)–(R5), for the regularized velocities and
pressures, with every input discharged.
theorem
CKN.Leray.leray_existence_direct_route
(ρ : RegMollifierProfile)
(a : Foundation.Parabolic.Vec3 → Foundation.Parabolic.Vec3)
:
IsInJ a →
∃ (u : Foundation.Parabolic.ParabolicPoint → Foundation.Parabolic.Vec3) (Du :
Foundation.Parabolic.ParabolicPoint → Fin 3 → Foundation.Parabolic.Vec3) (p :
Foundation.Parabolic.ParabolicPoint → ℝ),
IsGlobalLerayHopfSolution a u Du ∧ ∀ (q : ℝ), 5 / 2 < q → IsSuitableWeakSolution Set.univ (Set.Ioi 0) q u Du p 0
thm:leray by the direct route, for the regularized solutions with the
mollifier profile ρ.