Primitive zero-order bounds for the actual pulled-back flow gradient.
theorem
AVenhance.Infra.Section4.amnr_flowGrad_abs_le_of_lipschitz
{β : ℝ}
(I : Ingredients β)
{Φ : ℕ → ℝ → Homogenization.Vec 2 → ℝ}
(hΦ : IsStreamSeq I Φ)
(m : ℕ)
{L : ℝ}
(hL : ∀ (t : ℝ) (x y : Homogenization.Vec 2), ‖streamVel (Φ (m - 1)) t x - streamVel (Φ (m - 1)) t y‖ ≤ L * ‖x - y‖)
(l : ℤ)
(t : ℝ)
(x : Homogenization.Vec 2)
(k p : Fin 2)
:
Grönwall controls every coordinate of the actual flow gradient. The pullback evaluation needs no additional estimate on the inverse flow.
theorem
AVenhance.Infra.Section4.amnr_flowGrad_abs_le_on_cutoff_window
{β : ℝ}
(I : Ingredients β)
{Φ : ℕ → ℝ → Homogenization.Vec 2 → ℝ}
(hΦ : IsStreamSeq I Φ)
{m : ℕ}
(hm : 1 ≤ m)
{C : ℝ}
(hC : 0 ≤ C)
(hL :
∀ (t : ℝ) (x y : Homogenization.Vec 2),
‖streamVel (Φ (m - 1)) t x - streamVel (Φ (m - 1)) t y‖ ≤ C * a β I.Λ (m - 1) * ‖x - y‖)
(l : ℤ)
(t : ℝ)
(x : Homogenization.Vec 2)
(ht : |t - ↑l * tauPP β I.Λ m| ≤ tauPP β I.Λ m / 2 + tauP β I.Λ m)
(k p : Fin 2)
:
On every closed cutoff window, the source-scale Lipschitz estimate gives a uniform primitive flow-gradient bound, independent of m and l.