Analyticity of uniform limits on complex polydiscs, using the Cauchy integral formula and convergence of weighted integrals over compact sets.
theorem
KamProject.Arnold1963.analyticAt_cauchyIntegral
{n : ℕ}
{f : ComplexSpace n → ℂ}
{c w : ComplexSpace n}
{r : RealSpace n}
(hr : ∀ (i : Fin n), 0 ≤ r i)
(hf : ContinuousOn f (Set.univ.pi fun (i : Fin n) => Metric.closedBall (c i) (r i)))
(hw : ∀ (i : Fin n), w i ∈ Metric.ball (c i) (r i))
:
AnalyticAt ℂ (fun (a : ComplexSpace n) => ∯ (z : Fin n → ℂ) in T(c, r), cauchyKernel a z * f z) w
theorem
KamProject.Arnold1963.tendsto_weightedIntegral_of_uniform_compact
{X : Type u_1}
[TopologicalSpace X]
[MeasurableSpace X]
[OpensMeasurableSpace X]
{μ : MeasureTheory.Measure X}
[MeasureTheory.IsFiniteMeasureOnCompacts μ]
{K : Set X}
(hK : IsCompact K)
(hKm : MeasurableSet K)
{F : ℕ → X → ℂ}
{f a : X → ℂ}
(hF : ∀ (s : ℕ), ContinuousOn (F s) K)
(ha : ContinuousOn a K)
(hu : TendstoUniformlyOn F f Filter.atTop K)
:
theorem
KamProject.Arnold1963.analyticAt_uniform_limit_polydisc
{n : ℕ}
{F : ℕ → ComplexSpace n → ℂ}
{f : ComplexSpace n → ℂ}
{c : ComplexSpace n}
{R : ℝ}
(hR : 0 < R)
(hF : ∀ (s : ℕ), AnalyticOnNhd ℂ (F s) (Metric.closedBall c R))
(hu : TendstoUniformlyOn F f Filter.atTop (Metric.closedBall c R))
:
AnalyticAt ℂ f c
theorem
KamProject.Arnold1963.analyticOnNhd_uniform_limit
{n : ℕ}
{U : Set (ComplexSpace n)}
(hU : IsOpen U)
{F : ℕ → ComplexSpace n → ℂ}
{f : ComplexSpace n → ℂ}
(hF : ∀ (s : ℕ), AnalyticOnNhd ℂ (F s) U)
(hu : TendstoUniformlyOn F f Filter.atTop U)
:
AnalyticOnNhd ℂ f U