English
If V and W are ContDiff 𝕜 n, and m+1 ≤ n, then lieBracket 𝕜 V W is ContDiff 𝕜 m.
Русский
Если V и W гладкие на всем пространстве, и m+1 ≤ n, то скобка Ли [V, W] гладкая на уровне m.
LaTeX
$$$(hV: ContDiff 𝕜 n V) \\land (hW: ContDiff 𝕜 n W) \\land (hmn: m+1 \\le n) \\Rightarrow ContDiff 𝕜 m (lieBracket 𝕜 V W)$$$
Lean4
theorem _root_.ContDiff.lieBracket_vectorField {m n : WithTop ℕ∞} (hV : ContDiff 𝕜 n V) (hW : ContDiff 𝕜 n W)
(hmn : m + 1 ≤ n) : ContDiff 𝕜 m (lieBracket 𝕜 V W) :=
contDiff_iff_contDiffAt.2 (fun _ ↦ hV.contDiffAt.lieBracket_vectorField hW.contDiffAt hmn)