Uniform short-time interval #
The fixed Carleman constants and Gaussian threshold yield one time interval valid for every field with the prescribed growth rate.
theorem
ESS.bu_short_uniform_from_density_provider
(c₁ γ : ℝ)
(hc₁ : 0 < c₁)
(hγ : 0 < γ)
(hγsmall : γ < 1 / 12)
(hDensity :
∀ (M scale : ℝ),
0 < M →
M ≤ 1 / 10 ^ 12 →
1 / 10 ^ 12 / 2 ≤ M →
0 < scale →
scale ^ 2 ≤ γ →
∀ (w : CKN.Foundation.Parabolic.ParabolicPoint → CKN.Foundation.Parabolic.Vec3)
(Dw : CKN.Foundation.Parabolic.ParabolicPoint → Fin 3 → CKN.Foundation.Parabolic.Vec3)
(D2w : CKN.Foundation.Parabolic.ParabolicPoint → Fin 3 → Fin 3 → CKN.Foundation.Parabolic.Vec3)
(Dtw : CKN.Foundation.Parabolic.ParabolicPoint → CKN.Foundation.Parabolic.Vec3),
ContinuousOn w ({x : CKN.Foundation.Parabolic.Vec3 | 0 < x 2} ×ˢ Set.Ico 0 1) →
(∀ (x : CKN.Foundation.Parabolic.Vec3), 0 < x 2 → w (x, 0) = 0) →
CKN.HasSpaceTimeWeakDerivs {x : CKN.Foundation.Parabolic.Vec3 | 0 < x 2} (Set.Ioo 0 1) w Dw D2w
Dtw →
(∀ S ⊆ CKN.spaceTimeSet {x : CKN.Foundation.Parabolic.Vec3 | 0 < x 2} (Set.Ioo 0 1),
Bornology.IsBounded S →
∫⁻ (z : CKN.Foundation.Parabolic.ParabolicPoint) in S, ‖Dw z‖ₑ ^ 2 + ‖D2w z‖ₑ ^ 2 + ‖Dtw z‖ₑ ^ 2 < ⊤) →
(∀ᵐ (z :
CKN.Foundation.Parabolic.ParabolicPoint) ∂MeasureTheory.volume.restrict
(CKN.spaceTimeSet {x : CKN.Foundation.Parabolic.Vec3 | 0 < x 2} (Set.Ioo 0 1)), CKN.Foundation.Parabolic.vec3EuclideanNorm (ucWeakHeatVector D2w Dtw z) ≤ c₁ * (√(CKN.spatialGradientSq w Dw z) + CKN.Foundation.Parabolic.vec3EuclideanNorm (w z))) →
(∀ z ∈ CKN.spaceTimeSet {x : CKN.Foundation.Parabolic.Vec3 | 0 < x 2} (Set.Ioo 0 1),
CKN.Foundation.Parabolic.vec3EuclideanNorm (w z) ≤ Real.exp (M * CKN.Foundation.Parabolic.vec3EuclideanNorm z.1 ^ 2)) →
MeasureTheory.IntegrableOn (buShortTangentialDensity scale w Dw)
(buShortWideGapRegion scale) MeasureTheory.volume ∧ ∀ (a : ℝ),
0 ≤ a →
MeasureTheory.IntegrableOn (buShortWeightedPolynomialDensity scale a w Dw)
(buShortHighStrip scale) MeasureTheory.volume ∧ MeasureTheory.IntegrableOn (buShortWeightedDensity scale a w Dw)
(buShortHighStrip scale) MeasureTheory.volume)
:
∃ (γ₁ : ℝ),
0 < γ₁ ∧ γ₁ ≤ γ / 2 ∧ ∀ (A : ℝ),
0 ≤ A →
A ≤ 1 / 10 ^ 12 →
∀ (w : CKN.Foundation.Parabolic.ParabolicPoint → CKN.Foundation.Parabolic.Vec3)
(Dw : CKN.Foundation.Parabolic.ParabolicPoint → Fin 3 → CKN.Foundation.Parabolic.Vec3)
(D2w : CKN.Foundation.Parabolic.ParabolicPoint → Fin 3 → Fin 3 → CKN.Foundation.Parabolic.Vec3)
(Dtw : CKN.Foundation.Parabolic.ParabolicPoint → CKN.Foundation.Parabolic.Vec3),
ContinuousOn w ({x : CKN.Foundation.Parabolic.Vec3 | 0 < x 2} ×ˢ Set.Ico 0 1) →
(∀ (x : CKN.Foundation.Parabolic.Vec3), 0 < x 2 → w (x, 0) = 0) →
CKN.HasSpaceTimeWeakDerivs {x : CKN.Foundation.Parabolic.Vec3 | 0 < x 2} (Set.Ioo 0 1) w Dw D2w Dtw →
(∀ S ⊆ CKN.spaceTimeSet {x : CKN.Foundation.Parabolic.Vec3 | 0 < x 2} (Set.Ioo 0 1),
Bornology.IsBounded S →
∫⁻ (z : CKN.Foundation.Parabolic.ParabolicPoint) in S, ‖Dw z‖ₑ ^ 2 + ‖D2w z‖ₑ ^ 2 + ‖Dtw z‖ₑ ^ 2 < ⊤) →
(∀ᵐ (z :
CKN.Foundation.Parabolic.ParabolicPoint) ∂MeasureTheory.volume.restrict
(CKN.spaceTimeSet {x : CKN.Foundation.Parabolic.Vec3 | 0 < x 2} (Set.Ioo 0 1)), CKN.Foundation.Parabolic.vec3EuclideanNorm (ucWeakHeatVector D2w Dtw z) ≤ c₁ * (√(CKN.spatialGradientSq w Dw z) + CKN.Foundation.Parabolic.vec3EuclideanNorm (w z))) →
(∀ z ∈ CKN.spaceTimeSet {x : CKN.Foundation.Parabolic.Vec3 | 0 < x 2} (Set.Ioo 0 1),
CKN.Foundation.Parabolic.vec3EuclideanNorm (w z) ≤ Real.exp (A * CKN.Foundation.Parabolic.vec3EuclideanNorm z.1 ^ 2)) →
∀ (x : CKN.Foundation.Parabolic.Vec3), 0 < x 2 → ∀ (t : ℝ), 0 < t → t < γ₁ → w (x, t) = 0
Uniform short-time vanishing follows when the three Gaussian energy
densities are integrable below the Gaussian time threshold
(lem:bu-small-time).