Public statement.
theorem
AVenhance.lebron_step
(β C₀ : ℝ)
:
∃ (μ : ℝ) (C : ℝ),
0 < μ ∧ ∀ (I : Ingredients β),
I.Czeta ≤ C₀ →
I.Cxi ≤ C₀ →
I.Chat ≤ C₀ →
C ≤ ↑I.Λ →
∀ (Φ : ℕ → ℝ → Homogenization.Vec 2 → ℝ),
IsStreamSeq I Φ →
∀ κ ∈ permissibleSet β I.Λ,
∀ (M : ℕ),
1 ≤ M →
κ ∈ permittedInterval β I.Λ M →
∀ (R : ℝ),
0 < R →
∀ (θ₀ : Homogenization.Vec 2 → ℝ),
ContDiff ℝ (↑⊤) θ₀ →
IsZ2Periodic θ₀ →
Homogenization.MeanZeroOn unitCube θ₀ →
IsThetaAnalytic R θ₀ →
∀ (m : ℕ),
mTheta0 β I.Λ R ≤ m →
m ≤ M →
∀ (θm θprev : ℝ → Homogenization.Vec 2 → ℝ),
IsClassicalSol (streamVel (Φ m)) (I.kappaSeq κ M m)
(fun (x : ℝ) (x_1 : Homogenization.Vec 2) => 0) θ₀ θm →
IsClassicalSol (streamVel (Φ (m - 1))) (I.kappaSeq κ M (m - 1))
(fun (x : ℝ) (x_1 : Homogenization.Vec 2) => 0) θ₀ θprev →
HolderTimeL2Le μ
(C * epsilon β I.Λ (m - 1) ^ (delta β / 2) * √(l2NormSq θ₀ + gradNormSq (spaceGrad θ₀)))
fun (t : ℝ) (x : Homogenization.Vec 2) => θm t x - θprev t x
Remark 5.3 of the paper (r.LeBron) (e.continuous.indeed, 9041-9051), in the context of
p.indystepdown
(premises exactly those of step-down minus the iterate witness T):
‖θ_m − θ_{m−1}‖_{C^{0,μ}([0,1];L²)} ≤ C ε_{m−1}^{δ/2} ‖θ₀‖_{H¹} with μ, C depending only on β
(and the cutoff bound C₀).