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LeanPool.AnomalousDiffusion.AVenhance.Infra.Section5.RelativeError.RelativeInitial

with the actual initial corrector. The active flow derivative bound, corrector size and positive initial gradient trace are separate named inputs. No identity ansatz(0)=g is asserted.

theorem AVenhance.Infra.Section5.RelativeError.relative_flowGrad_entry_le_two {β : ℝ} (I : Ingredients β) {Φ : ℕ → ℝ → Homogenization.Vec 2 → ℝ} (hΦ : IsStreamSeq I Φ) (m : ℕ) (l : ℤ) (hDX : ∀ (y : Homogenization.Vec 2), ‖fderiv ℝ (I.xFlow hΦ m l 0) y‖ ≤ 2) (x : Homogenization.Vec 2) (i j : Fin 2) :
|I.flowGrad hΦ m l 0 x i j| ≤ 2

The active-flow operator bound used by implies the entrywise bound in the derivative-row convention.

theorem AVenhance.Infra.Section5.RelativeError.relative_initial_corrector_bound {β : ℝ} (I : Ingredients β) {Φ : ℕ → ℝ → Homogenization.Vec 2 → ℝ} (hΦ : IsStreamSeq I Φ) (m : ℕ) (κ : ℝ) {g : Homogenization.Vec 2 → ℝ} (hg : ContDiff ℝ (↑⊤) g) (T : ℝ → Homogenization.Vec 2 → ℝ) (hT0 : T 0 = g) {B K : ℝ} (hB : 0 ≤ B) (hK : 0 ≤ K) (hChi : ∀ (k : ℤ), I.xiMK m k 0 ≠ 0 → ∀ (x : Homogenization.Vec 2) (i : Fin 2), |I.chiTilde hΦ m κ k 0 x i| ≤ B) (hFlow2 : ∀ (k : ℤ), I.xiMK m k 0 ≠ 0 → ∀ (x : Homogenization.Vec 2) (i j : Fin 2), |I.flowGrad hΦ m (lIdx β I.Λ m k) 0 x i j| ≤ 2) (hCutoff : ∑ k ∈ ⋯.toFinset, |I.xiMK m k 0| ≤ K) :
√(l2NormSq fun (x : Homogenization.Vec 2) => ∑' (k : ℤ), I.xiMK m k 0 * Homogenization.vecDot (I.chiTilde hΦ m κ k 0 x) (spaceGrad (fun (y : Homogenization.Vec 2) => T 0 (I.xFlow hΦ m (lIdx β I.Λ m k) 0 y)) (I.xFlowInv hΦ m (lIdx β I.Λ m k) 0 x))) ≤ 8 * B * K * √(gradNormSq (spaceGrad g))

The initial corrector series has only the positive derivative of g. The two-dimensional conversion costs 8 with entrywise |DX|<=2.