fpvandoorn/carleson
Source indexedlemma · leanprover/lean4:v4.32.0
dist_mem_Icc_of_mem_tsupport_Ks
Carleson.Psi · Carleson/Psi.lean:358 to 372
Mathematical statement
Exact Lean statement
lemma dist_mem_Icc_of_mem_tsupport_Ks {s : ℤ} {x : X × X}
(h : x ∈ tsupport fun x ↦ (Ks s x.1 x.2)) :
dist x.1 x.2 ∈ Icc ((D ^ (s - 1) : ℝ) / 4) (D ^ s / 2)Complete declaration
Lean source
Full Lean sourceLean 4
lemma dist_mem_Icc_of_mem_tsupport_Ks {s : ℤ} {x : X × X} (h : x ∈ tsupport fun x ↦ (Ks s x.1 x.2)) : dist x.1 x.2 ∈ Icc ((D ^ (s - 1) : ℝ) / 4) (D ^ s / 2) := by set C := support fun (x : X × X) ↦ Ks s x.1 x.2 have hcont : Continuous (fun (x : X × X) ↦ dist x.1 x.2) := by continuity have hC : (fun (x : X × X) ↦ dist x.1 x.2) '' C ⊆ Icc ((D ^ (s - 1) : ℝ) / 4) (D ^ s / 2) := by intro r hr simp only [mem_image, mem_support, C] at hr obtain ⟨x, hx, rfl⟩ := hr exact dist_mem_Icc_of_Ks_ne_zero hx have hC' : (fun (x : X × X) ↦ dist x.1 x.2) '' (tsupport fun x ↦ Ks s x.1 x.2) ⊆ Icc ((D ^ (s - 1) : ℝ) / 4) (D ^ s / 2) := subset_trans (image_closure_subset_closure_image hcont) ((isClosed_Icc.closure_subset_iff).mpr hC) exact hC' (mem_image_of_mem (fun x ↦ dist x.1 x.2) h)