Module: Mathlib.MeasureTheory.Function.ConditionalExpectation.AEMeasurable

Goal state before:
pp: case refine_1
α : Type u_1
F : Type u_2
p : ℝ≥0∞
inst✝² : NormedAddCommGroup F
m m0 : MeasurableSpace α
μ : Measure α
inst✝¹ : Fact (1 ≤ p)
inst✝ : NormedSpace ℝ F
hm : m ≤ m0
hp_ne_top : p ≠ ∞
P : ↥(Lp F p μ) → Prop
h_ind : ∀ (c : F) {s : Set α} (hs : MeasurableSet s) (hμs : μ s < ∞), P ↑(simpleFunc.indicatorConst p ⋯ ⋯ c)
h_add :
  ∀ ⦃f g : α → F⦄ (hf : MemLp f p μ) (hg : MemLp g p μ),
    AEStronglyMeasurable f μ →
      AEStronglyMeasurable g μ →
        Disjoint (Function.support f) (Function.support g) →
          P (MemLp.toLp f hf) → P (MemLp.toLp g hg) → P (MemLp.toLp f hf + MemLp.toLp g hg)
h_closed : IsClosed {f | P ↑f}
f : ↥(Lp F p μ)
hf : AEStronglyMeasurable (↑↑f) μ
f' : ↥(lpMeas F ℝ m p μ) := ⟨f, hf⟩
g : ↥(Lp F p (μ.trim hm)) := (lpMeasToLpTrimLie F ℝ p μ hm) f'
hfg : f' = (lpMeasToLpTrimLie F ℝ p μ hm).symm g
⊢ ∀ (c : F) {s : Set α} (hs : MeasurableSet s) (hμs : (μ.trim hm) s < ∞),
    P ↑((lpMeasToLpTrimLie F ℝ p μ hm).symm ↑(simpleFunc.indicatorConst p hs ⋯ c))

pp: case refine_2
α : Type u_1
F : Type u_2
p : ℝ≥0∞
inst✝² : NormedAddCommGroup F
m m0 : MeasurableSpace α
μ : Measure α
inst✝¹ : Fact (1 ≤ p)
inst✝ : NormedSpace ℝ F
hm : m ≤ m0
hp_ne_top : p ≠ ∞
P : ↥(Lp F p μ) → Prop
h_ind : ∀ (c : F) {s : Set α} (hs : MeasurableSet s) (hμs : μ s < ∞), P ↑(simpleFunc.indicatorConst p ⋯ ⋯ c)
h_add :
  ∀ ⦃f g : α → F⦄ (hf : MemLp f p μ) (hg : MemLp g p μ),
    AEStronglyMeasurable f μ →
      AEStronglyMeasurable g μ →
        Disjoint (Function.support f) (Function.support g) →
          P (MemLp.toLp f hf) → P (MemLp.toLp g hg) → P (MemLp.toLp f hf + MemLp.toLp g hg)
h_closed : IsClosed {f | P ↑f}
f : ↥(Lp F p μ)
hf : AEStronglyMeasurable (↑↑f) μ
f' : ↥(lpMeas F ℝ m p μ) := ⟨f, hf⟩
g : ↥(Lp F p (μ.trim hm)) := (lpMeasToLpTrimLie F ℝ p μ hm) f'
hfg : f' = (lpMeasToLpTrimLie F ℝ p μ hm).symm g
⊢ ∀ ⦃f g : α → F⦄ (hf : MemLp f p (μ.trim hm)) (hg : MemLp g p (μ.trim hm)),
    Disjoint (Function.support f) (Function.support g) →
      P ↑((lpMeasToLpTrimLie F ℝ p μ hm).symm (MemLp.toLp f hf)) →
        P ↑((lpMeasToLpTrimLie F ℝ p μ hm).symm (MemLp.toLp g hg)) →
          P ↑((lpMeasToLpTrimLie F ℝ p μ hm).symm (MemLp.toLp f hf + MemLp.toLp g hg))

pp: case refine_3
α : Type u_1
F : Type u_2
p : ℝ≥0∞
inst✝² : NormedAddCommGroup F
m m0 : MeasurableSpace α
μ : Measure α
inst✝¹ : Fact (1 ≤ p)
inst✝ : NormedSpace ℝ F
hm : m ≤ m0
hp_ne_top : p ≠ ∞
P : ↥(Lp F p μ) → Prop
h_ind : ∀ (c : F) {s : Set α} (hs : MeasurableSet s) (hμs : μ s < ∞), P ↑(simpleFunc.indicatorConst p ⋯ ⋯ c)
h_add :
  ∀ ⦃f g : α → F⦄ (hf : MemLp f p μ) (hg : MemLp g p μ),
    AEStronglyMeasurable f μ →
      AEStronglyMeasurable g μ →
        Disjoint (Function.support f) (Function.support g) →
          P (MemLp.toLp f hf) → P (MemLp.toLp g hg) → P (MemLp.toLp f hf + MemLp.toLp g hg)
h_closed : IsClosed {f | P ↑f}
f : ↥(Lp F p μ)
hf : AEStronglyMeasurable (↑↑f) μ
f' : ↥(lpMeas F ℝ m p μ) := ⟨f, hf⟩
g : ↥(Lp F p (μ.trim hm)) := (lpMeasToLpTrimLie F ℝ p μ hm) f'
hfg : f' = (lpMeasToLpTrimLie F ℝ p μ hm).symm g
⊢ IsClosed {f | P ↑((lpMeasToLpTrimLie F ℝ p μ hm).symm f)}

Tactic:
· intro b t ht hμt
    rw [@Lp.simpleFunc.coe_indicatorConst _ _ m, lpMeasToLpTrimLie_symm_indicator ht hμt.ne b]
    have hμt' : μ t < ∞ := (le_trim hm).trans_lt hμt
    specialize h_ind b ht hμt'
    rwa [Lp.simpleFunc.coe_indicatorConst] at h_ind

Goal state after:
case refine_2
α : Type u_1
F : Type u_2
p : ℝ≥0∞
inst✝² : NormedAddCommGroup F
m m0 : MeasurableSpace α
μ : Measure α
inst✝¹ : Fact (1 ≤ p)
inst✝ : NormedSpace ℝ F
hm : m ≤ m0
hp_ne_top : p ≠ ∞
P : ↥(Lp F p μ) → Prop
h_ind : ∀ (c : F) {s : Set α} (hs : MeasurableSet s) (hμs : μ s < ∞), P ↑(simpleFunc.indicatorConst p ⋯ ⋯ c)
h_add :
  ∀ ⦃f g : α → F⦄ (hf : MemLp f p μ) (hg : MemLp g p μ),
    AEStronglyMeasurable f μ →
      AEStronglyMeasurable g μ →
        Disjoint (Function.support f) (Function.support g) →
          P (MemLp.toLp f hf) → P (MemLp.toLp g hg) → P (MemLp.toLp f hf + MemLp.toLp g hg)
h_closed : IsClosed {f | P ↑f}
f : ↥(Lp F p μ)
hf : AEStronglyMeasurable (↑↑f) μ
f' : ↥(lpMeas F ℝ m p μ) := ⟨f, hf⟩
g : ↥(Lp F p (μ.trim hm)) := (lpMeasToLpTrimLie F ℝ p μ hm) f'
hfg : f' = (lpMeasToLpTrimLie F ℝ p μ hm).symm g
⊢ ∀ ⦃f g : α → F⦄ (hf : MemLp f p (μ.trim hm)) (hg : MemLp g p (μ.trim hm)),
    Disjoint (Function.support f) (Function.support g) →
      P ↑((lpMeasToLpTrimLie F ℝ p μ hm).symm (MemLp.toLp f hf)) →
        P ↑((lpMeasToLpTrimLie F ℝ p μ hm).symm (MemLp.toLp g hg)) →
          P ↑((lpMeasToLpTrimLie F ℝ p μ hm).symm (MemLp.toLp f hf + MemLp.toLp g hg))

case refine_3
α : Type u_1
F : Type u_2
p : ℝ≥0∞
inst✝² : NormedAddCommGroup F
m m0 : MeasurableSpace α
μ : Measure α
inst✝¹ : Fact (1 ≤ p)
inst✝ : NormedSpace ℝ F
hm : m ≤ m0
hp_ne_top : p ≠ ∞
P : ↥(Lp F p μ) → Prop
h_ind : ∀ (c : F) {s : Set α} (hs : MeasurableSet s) (hμs : μ s < ∞), P ↑(simpleFunc.indicatorConst p ⋯ ⋯ c)
h_add :
  ∀ ⦃f g : α → F⦄ (hf : MemLp f p μ) (hg : MemLp g p μ),
    AEStronglyMeasurable f μ →
      AEStronglyMeasurable g μ →
        Disjoint (Function.support f) (Function.support g) →
          P (MemLp.toLp f hf) → P (MemLp.toLp g hg) → P (MemLp.toLp f hf + MemLp.toLp g hg)
h_closed : IsClosed {f | P ↑f}
f : ↥(Lp F p μ)
hf : AEStronglyMeasurable (↑↑f) μ
f' : ↥(lpMeas F ℝ m p μ) := ⟨f, hf⟩
g : ↥(Lp F p (μ.trim hm)) := (lpMeasToLpTrimLie F ℝ p μ hm) f'
hfg : f' = (lpMeasToLpTrimLie F ℝ p μ hm).symm g
⊢ IsClosed {f | P ↑((lpMeasToLpTrimLie F ℝ p μ hm).symm f)}