fpvandoorn/carleson
Source indexedlemma · leanprover/lean4:v4.32.0
LipschitzOnWith.of_iLipENorm_ne_top
Carleson.LipschitzNorm · Carleson/LipschitzNorm.lean:75 to 100
Mathematical statement
Exact Lean statement
lemma LipschitzOnWith.of_iLipENorm_ne_top (hφ : iLipENorm φ z R ≠ ⊤) :
LipschitzOnWith (iLipNNNorm φ z R / R.toNNReal) φ (ball z R)Complete declaration
Lean source
Full Lean sourceLean 4
lemma LipschitzOnWith.of_iLipENorm_ne_top (hφ : iLipENorm φ z R ≠ ⊤) : LipschitzOnWith (iLipNNNorm φ z R / R.toNNReal) φ (ball z R) := by intro x hx y hy have hR : 0 < R := by simp only [mem_ball] at hx apply dist_nonneg.trans_lt hx rcases eq_or_ne x y with rfl | hne · simp have : (ENNReal.ofReal R) * (‖φ x - φ y‖ₑ / edist x y) ≤ iLipENorm φ z R := calc (ENNReal.ofReal R) * (‖φ x - φ y‖ₑ / (edist x y)) _ ≤ (ENNReal.ofReal R) * ⨆ (x ∈ ball z R) (y ∈ ball z R) (_ : x ≠ y), (‖φ x - φ y‖ₑ / edist x y) := by gcongr simp only [ne_eq, le_iSup_iff, iSup_le_iff] tauto _ ≤ _ := le_add_self rw [edist_eq_enorm_sub, ENNReal.coe_div (by simp [hR]), iLipNNNorm, coe_toNNReal hφ] rw [← ENNReal.div_le_iff_le_mul]; rotate_left · have : edist x y ≠ 0 := by simp [hne] simp [this] · simp [edist_ne_top] rw [ENNReal.le_div_iff_mul_le]; rotate_left · simp [hR] · simp convert this using 1 simp only [ENNReal.ofReal, mul_comm]