Receding Transport Pairing Bound #
Supporting results for the Constantin–Ignatova–Vicol axisymmetric regularity theorem.
theorem
CIV.transport_term_pairing_bound_fixed
{C h lam rc zc : ℝ}
(hC : 0 ≤ C)
(hh0 : 0 ≤ h)
(hh1 : h ≤ 1 / 2)
(hlam : 0 < lam)
(hdelta : lam ^ (2 * h) ≤ 1)
{u : CKN.Foundation.Parabolic.ParabolicPoint → CKN.Foundation.Parabolic.Vec3}
(hb : AnisotropicBounds C h u)
(hu : ContDiffOn ℝ (↑⊤) (fun (z : CKN.Foundation.Parabolic.Vec3 × ℝ) => u z) unitCylinder)
{K : Set (ℝ × ℝ)}
(hK : IsCompact K)
{τ : ℝ}
(htau : τ ≤ -1)
(hmem : ∀ y ∈ K, zoomPointRec lam h rc zc (y, τ) ∈ unitCylinder)
(ψ : ℝ × ℝ → ℝ)
(hψ : ContDiff ℝ (↑⊤) ψ)
(hψc : HasCompactSupport ψ)
(hψU : tsupport ψ ⊆ interior K)
(B : ℝ)
:
0 ≤ B →
∀ (hψB : ∀ (y : ℝ × ℝ), |ψ y| ≤ B ∧ ‖fderiv ℝ ψ y‖ ≤ B ∧ ‖fderiv ℝ (fderiv ℝ ψ) y‖ ≤ B),
|∫ (y : ℝ × ℝ), -(dr (fun (q : (ℝ × ℝ) × ℝ) => zoomVRec lam h rc zc u q * zoomTheta lam h rc zc u q) (y, τ) + dz (fun (q : (ℝ × ℝ) × ℝ) => zoomWRec lam h rc zc u q * zoomTheta lam h rc zc u q) (y, τ)) * ψ y| ≤ 4 * C ^ 2 * (MeasureTheory.volume K).toReal * B
The transport/divergence-term pairing bound at a fixed zoom scale: the integral of
−(∂_R(V_nΘ_n) + ∂_Z(W_nΘ_n)), the perfect-divergence transport term of
zoomTheta_pde_divergenceForm, against a test function supported in the interior of a
compact set K is bounded by 4C² times the bound B on ψ and its first two
derivatives, times the volume of K.
theorem
CIV.transport_term_pairing_bound
{C h : ℝ}
(hC : 0 ≤ C)
(hh0 : 0 ≤ h)
(hh1 : h ≤ 1 / 2)
{rc zc : ℝ}
(lam : ℕ → ℝ)
(hlam_pos : ∀ (n : ℕ), 0 < lam n)
(hlam_le : ∀ᶠ (n : ℕ) in Filter.atTop, lam n ^ (2 * h) ≤ 1)
{u : CKN.Foundation.Parabolic.ParabolicPoint → CKN.Foundation.Parabolic.Vec3}
(hb : AnisotropicBounds C h u)
(hu : ContDiffOn ℝ (↑⊤) (fun (z : CKN.Foundation.Parabolic.Vec3 × ℝ) => u z) unitCylinder)
{K : Set (ℝ × ℝ)}
(hK : IsCompact K)
{τ : ℝ}
(htau : τ ≤ -1)
(hmem : ∀ᶠ (n : ℕ) in Filter.atTop, ∀ y ∈ K, zoomPointRec (lam n) h rc zc (y, τ) ∈ unitCylinder)
:
∃ (C₀ : ℝ),
0 ≤ C₀ ∧ ∀ (ψ : ℝ × ℝ → ℝ),
ContDiff ℝ (↑⊤) ψ →
HasCompactSupport ψ →
tsupport ψ ⊆ interior K →
∀ (B : ℝ),
0 ≤ B →
(∀ (y : ℝ × ℝ), |ψ y| ≤ B ∧ ‖fderiv ℝ ψ y‖ ≤ B ∧ ‖fderiv ℝ (fderiv ℝ ψ) y‖ ≤ B) →
∀ᶠ (n : ℕ) in Filter.atTop, |∫ (y : ℝ × ℝ), -(dr (fun (q : (ℝ × ℝ) × ℝ) => zoomVRec (lam n) h rc zc u q * zoomTheta (lam n) h rc zc u q)
(y, τ) + dz
(fun (q : (ℝ × ℝ) × ℝ) =>
zoomWRec (lam n) h rc zc u q * zoomTheta (lam n) h rc zc u q)
(y, τ)) * ψ y| ≤ C₀ * B
The eventual-in-n pairing bound for the transport/divergence term: C₀ := 4C² is
chosen before n, matching the eventual form of the time-pairing estimate hpair.