@@ -295,7 +295,6 @@ section UniformIntegrable
295295variable {E : Type *} [MeasurableSpace E] [NormedAddCommGroup E] [BorelSpace E]
296296 {μ : Measure α} [IsFiniteMeasure μ]
297297
298- set_option backward.isDefEq.respectTransparency false in
299298/-- This lemma is superseded by `MemLp.uniformIntegrable_of_identDistrib` which only requires
300299`AEStronglyMeasurable`. -/
301300theorem MemLp.uniformIntegrable_of_identDistrib_aux {ι : Type *} {f : ι → α → E} {j : ι} {p : ℝ≥0 ∞}
@@ -304,21 +303,21 @@ theorem MemLp.uniformIntegrable_of_identDistrib_aux {ι : Type*} {f : ι → α
304303 refine uniformIntegrable_of' hp hp' hfmeas fun ε hε => ?_
305304 by_cases hι : Nonempty ι
306305 swap; · exact ⟨0 , fun i => False.elim (hι <| Nonempty.intro i)⟩
307- obtain ⟨C, hC₁ , hC₂⟩ := hℒp.eLpNorm_indicator_norm_ge_pos_le (hfmeas _) hε
308- refine ⟨⟨C, hC₁.le⟩ , fun i => le_trans (le_of_eq ?_) hC₂⟩
309- have : {x | (⟨C, hC₁.le⟩ : ℝ≥ 0 ) ≤ ‖f i x‖₊} = {x | C ≤ ‖f i x‖} := by
306+ obtain ⟨C, - , hC₂⟩ := hℒp.eLpNorm_indicator_norm_ge_pos_le (hfmeas _) hε
307+ refine ⟨C.toNNReal , fun i ↦ le_trans (le_of_eq ?_) hC₂⟩
308+ have : {x | C.toNNReal ≤ ‖f i x‖₊} = {x | C ≤ ‖f i x‖} := by
310309 ext x
311- simp_rw [← norm_toNNReal]
312- exact Real.le_toNNReal_iff_coe_le (norm_nonneg _)
310+ simp_rw [Set.mem_ofPred_eq, Real.toNNReal_le_iff_le_coe, coe_nnnorm]
313311 rw [this, ← eLpNorm_norm, ← eLpNorm_norm (Set.indicator _ _)]
314312 simp_rw [norm_indicator_eq_indicator_norm, coe_nnnorm]
315- let F : E → ℝ := (fun x : E => if (⟨C, hC₁.le⟩ : ℝ≥ 0 ) ≤ ‖x‖₊ then ‖x‖ else 0 )
313+ let F : E → ℝ := (fun x : E ↦ if C.toNNReal ≤ ‖x‖₊ then ‖x‖ else 0 )
316314 have F_meas : Measurable F := by
317315 apply measurable_norm.indicator (measurableSet_le measurable_const measurable_nnnorm)
318316 have : ∀ k, (fun x ↦ Set.indicator {x | C ≤ ‖f k x‖} (fun a ↦ ‖f k a‖) x) = F ∘ f k := by
319317 intro k
320318 ext x
321- simp only [Set.indicator, Set.mem_ofPred_eq]; norm_cast
319+ simp only [F, Set.indicator, Set.mem_ofPred_eq, Function.comp_apply,
320+ Real.toNNReal_le_iff_le_coe, coe_nnnorm]
322321 rw [this, this, ← eLpNorm_map_measure F_meas.aestronglyMeasurable (hf i).aemeasurable_fst,
323322 (hf i).map_eq, eLpNorm_map_measure F_meas.aestronglyMeasurable (hf j).aemeasurable_fst]
324323
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