The lower-time derivative error #
On the cutoff support the time-transition indicator agrees with the indicator of the larger trace cylinder.
theorem
ESS.bu_short_early_error_tendsto_zero
(M scale R a : ℝ)
(hM : 0 < M)
(hscale : 0 < scale)
(hscale1 : scale ≤ 1)
(hR : 0 < R)
(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)
(hcont : ContinuousOn w ({x : CKN.Foundation.Parabolic.Vec3 | 0 < x 2} ×ˢ Set.Ico 0 1))
(hinit : ∀ (x : CKN.Foundation.Parabolic.Vec3), 0 < x 2 → w (x, 0) = 0)
(hweak : CKN.HasSpaceTimeWeakDerivs {x : CKN.Foundation.Parabolic.Vec3 | 0 < x 2} (Set.Ioo 0 1) w Dw D2w Dtw)
(hL2 :
∀ 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 < ⊤)
(hgrowth :
∀ 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))
:
Filter.Tendsto
(fun (ε : ℝ) =>
have K := buCutSupportSet (buShortFullCutoff scale R hR ε);
have v := buAffineField (-scale ^ 2 / 2) scale w;
∫ (z : CKN.Foundation.Parabolic.ParabolicPoint) in K, buShortCarlemanWeight a z * (if 1 / 2 + ε ≤ z.2 ∧ z.2 ≤ 1 / 2 + 2 * ε then 8 / ε * CKN.Foundation.Parabolic.vec3EuclideanNorm (v z)
else 0) ^ 2)
(nhdsWithin 0 (Set.Ioi 0)) (nhds 0)
The squared lower-time derivative contribution to the cutoff heat error vanishes after integration.