English
The uniformity on α equals the comap of the neighborhood filter at 1 under the map (x, y) ↦ y/x.
Русский
Унииформность на α равна обратному образу фильтра соседних окрестностей в единице по отображению (x, y) ↦ y/x.
LaTeX
$$$\\mathcal{U}(\\alpha) = \\mathrm{comap}\\bigl(\\lambda x:(\\alpha \\times \\alpha).\\, x_2 / x_1\\bigr)(\\mathcal{N}(1))$$$
Lean4
@[to_additive UniformContinuous.const_zsmul]
theorem zpow_const [UniformSpace β] {f : β → α} (hf : UniformContinuous f) : ∀ n : ℤ, UniformContinuous fun x => f x ^ n
| (n : ℕ) => by
simp_rw [zpow_natCast]
exact hf.pow_const _
| Int.negSucc n => by
simp_rw [zpow_negSucc]
exact (hf.pow_const _).inv