openAI-math-dataset / lean /OAI /Analysis /AncientFlat /Evolution /DilationContinuity.lean
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Add lean source and binary files (part 10)
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import OAI.Analysis.AncientFlat.Evolution.DilationCore
namespace OAI
noncomputable section
open Set Filter
open scoped Topology ZeroAtInfty BoundedContinuousFunction
namespace ParametrixDilation
variable {V : Type} [NormedAddCommGroup V] [NormedSpace ℝ V]
lemma dist_dil_le (t : ℝ) (f g : C₀(V,ℂ)) : dist (dil t f) (dil t g)≤dist f g := by
let : NormedAddCommGroup C₀(V,ℂ) := inferInstance
let : NormedSpace ℂ C₀(V,ℂ) := inferInstance
rw [dist_eq_norm,dist_eq_norm,←map_sub]
exact norm_dil_le t (f-g)
lemma tendsto_dil_apply {ι : Type*} {l : Filter ι} {r : ι → ℝ} {u : ι → C₀(V,ℂ)}
{r₀ : ℝ} {u₀ : C₀(V,ℂ)} (hr : Tendsto r l (𝓝 r₀)) (hu : Tendsto u l (𝓝 u₀)) :
Tendsto (fun i => dil (r i) (u i)) l (𝓝 (dil r₀ u₀)) := by
apply tendsto_iff_dist_tendsto_zero.mpr
have h₁ := tendsto_iff_dist_tendsto_zero.mp hu
have h₂ := tendsto_iff_dist_tendsto_zero.mp (((continuous_dil u₀).tendsto r₀).comp hr)
apply squeeze_zero (fun i => dist_nonneg) (fun i => ?_) (by simpa using h₁.add h₂)
exact (dist_triangle _ (dil (r i) u₀) _).trans
(add_le_add (dist_dil_le (r i) (u i) u₀) le_rfl)
lemma continuousOn_dil_apply {u : ℝ → C₀(V,ℂ)} {I : Set ℝ}
(hu : ContinuousOn u I) : ContinuousOn (fun t => dil t (u t)) I := by
intro t ht
exact tendsto_dil_apply continuousWithinAt_id (hu t ht)
end ParametrixDilation
end
end OAI