High-order whole-space Sobolev product estimate #
At integer order at least three, every Leibniz term has a factor
with at least two derivatives to spare. Whole-space H² → L∞
therefore bounds the product in the ordered Sobolev energy.
theorem
ESS.lps_smooth_leibniz_normSq_high
(m : ℕ)
(hm : 3 ≤ m)
:
∃ (C : ℝ),
0 ≤ C ∧ ∀ (f g : CKN.Foundation.Parabolic.Vec3 → ℝ),
ContDiff ℝ (↑⊤) f →
ContDiff ℝ (↑⊤) g →
(∀ (α : List (Fin 3)), α.length ≤ m → MeasureTheory.MemLp (CKN.wordDeriv α f) 2 MeasureTheory.volume) →
(∀ (α : List (Fin 3)), α.length ≤ m → MeasureTheory.MemLp (CKN.wordDeriv α g) 2 MeasureTheory.volume) →
(∀ (α : List (Fin 3)),
α.length ≤ m →
MeasureTheory.Integrable
(fun (x : CKN.Foundation.Parabolic.Vec3) =>
CKN.sobolevLeibnizFamily α (fun (β : List (Fin 3)) => CKN.wordDeriv β f)
(fun (β : List (Fin 3)) => CKN.wordDeriv β g) x ^ 2)
MeasureTheory.volume) ∧ (CKN.sobolevNormSqOn m Set.univ fun (α : List (Fin 3)) =>
CKN.sobolevLeibnizFamily α (fun (β : List (Fin 3)) => CKN.wordDeriv β f) fun (β : List (Fin 3)) =>
CKN.wordDeriv β g) ≤ (C * CKN.sobolevNormSqOn m Set.univ fun (α : List (Fin 3)) => CKN.wordDeriv α f) * CKN.sobolevNormSqOn m Set.univ fun (α : List (Fin 3)) => CKN.wordDeriv α g
The ordered Leibniz family of two smooth H^m functions has
square-integrable derivatives through order m ≥ 3, with an H^m
algebra bound (eq:lps-Hm-energy).
theorem
ESS.lps_smooth_product_normSq_high
(m : ℕ)
(hm : 3 ≤ m)
:
∃ (C : ℝ),
0 ≤ C ∧ ∀ (f g : CKN.Foundation.Parabolic.Vec3 → ℝ),
ContDiff ℝ (↑⊤) f →
ContDiff ℝ (↑⊤) g →
(∀ (α : List (Fin 3)), α.length ≤ m → MeasureTheory.MemLp (CKN.wordDeriv α f) 2 MeasureTheory.volume) →
(∀ (α : List (Fin 3)), α.length ≤ m → MeasureTheory.MemLp (CKN.wordDeriv α g) 2 MeasureTheory.volume) →
(∀ (α : List (Fin 3)),
α.length ≤ m →
MeasureTheory.MemLp (CKN.wordDeriv α fun (x : CKN.Foundation.Parabolic.Vec3) => f x * g x) 2
MeasureTheory.volume) ∧ (CKN.sobolevNormSqOn m Set.univ fun (α : List (Fin 3)) =>
CKN.wordDeriv α fun (x : CKN.Foundation.Parabolic.Vec3) => f x * g x) ≤ (C * CKN.sobolevNormSqOn m Set.univ fun (α : List (Fin 3)) => CKN.wordDeriv α f) * CKN.sobolevNormSqOn m Set.univ fun (α : List (Fin 3)) => CKN.wordDeriv α g
Smooth multiplication is bounded in the ordered whole-space H^m
norm for every integer m ≥ 3 (eq:lps-Hm-energy).