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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

Canonical source
Full Lean sourceLean 4
lemma dist_mem_Icc_of_mem_tsupport_Ks {s : } {x : X × X}    (h : x  tsupport fun x  (Ks s x.1 x.2)) :    dist x.1 x.2  Icc ((D ^ (s - 1) : ) / 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) : ) / 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) : ) / 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)