Module: Mathlib.Probability.Independence.Kernel.IndepFun

Goal state before:
pp: case pos
α : Type u_1
Ω : Type u_2
β : Type u_4
γ : Type u_6
mα : MeasurableSpace α
mΩ : MeasurableSpace Ω
κ : Kernel α Ω
μ : Measure α
mβ : MeasurableSpace β
mγ : MeasurableSpace γ
inst✝¹ : IsFiniteMeasure μ
inst✝ : IsFiniteKernel κ
f : Ω → β
g : Ω → γ
hf : Measurable f
hg : Measurable g
h :
  ∀ (s : Set β) (t : Set γ),
    MeasurableSet s → MeasurableSet t → ∀ᵐ (a : α) ∂μ, (κ a) (f ⁻¹' s ∩ g ⁻¹' t) = (κ a) (f ⁻¹' s) * (κ a) (g ⁻¹' t)
u : Set α
s : Set β
t : Set γ
hu : MeasurableSet u
hs : MeasurableSet s
ht : MeasurableSet t
h_set_eq : ∀ (ω : α), Prod.mk ω ⁻¹' u ×ˢ s ×ˢ t = if ω ∈ u then s ×ˢ t else ∅
ω : α
hω : (κ ω) (f ⁻¹' s ∩ g ⁻¹' t) = (κ ω) (f ⁻¹' s) * (κ ω) (g ⁻¹' t)
hωu : ω ∈ u
⊢ ((κ.map fun ω ↦ (f ω, g ω)) ω) (if ω ∈ u then s ×ˢ t else ∅) = ((κ.map f ×ₖ κ.map g) ω) (if ω ∈ u then s ×ˢ t else ∅)

pp: case neg
α : Type u_1
Ω : Type u_2
β : Type u_4
γ : Type u_6
mα : MeasurableSpace α
mΩ : MeasurableSpace Ω
κ : Kernel α Ω
μ : Measure α
mβ : MeasurableSpace β
mγ : MeasurableSpace γ
inst✝¹ : IsFiniteMeasure μ
inst✝ : IsFiniteKernel κ
f : Ω → β
g : Ω → γ
hf : Measurable f
hg : Measurable g
h :
  ∀ (s : Set β) (t : Set γ),
    MeasurableSet s → MeasurableSet t → ∀ᵐ (a : α) ∂μ, (κ a) (f ⁻¹' s ∩ g ⁻¹' t) = (κ a) (f ⁻¹' s) * (κ a) (g ⁻¹' t)
u : Set α
s : Set β
t : Set γ
hu : MeasurableSet u
hs : MeasurableSet s
ht : MeasurableSet t
h_set_eq : ∀ (ω : α), Prod.mk ω ⁻¹' u ×ˢ s ×ˢ t = if ω ∈ u then s ×ˢ t else ∅
ω : α
hω : (κ ω) (f ⁻¹' s ∩ g ⁻¹' t) = (κ ω) (f ⁻¹' s) * (κ ω) (g ⁻¹' t)
hωu : ω ∉ u
⊢ ((κ.map fun ω ↦ (f ω, g ω)) ω) (if ω ∈ u then s ×ˢ t else ∅) = ((κ.map f ×ₖ κ.map g) ω) (if ω ∈ u then s ×ˢ t else ∅)

Tactic:
swap

Goal state after:
case neg
α : Type u_1
Ω : Type u_2
β : Type u_4
γ : Type u_6
mα : MeasurableSpace α
mΩ : MeasurableSpace Ω
κ : Kernel α Ω
μ : Measure α
mβ : MeasurableSpace β
mγ : MeasurableSpace γ
inst✝¹ : IsFiniteMeasure μ
inst✝ : IsFiniteKernel κ
f : Ω → β
g : Ω → γ
hf : Measurable f
hg : Measurable g
h :
  ∀ (s : Set β) (t : Set γ),
    MeasurableSet s → MeasurableSet t → ∀ᵐ (a : α) ∂μ, (κ a) (f ⁻¹' s ∩ g ⁻¹' t) = (κ a) (f ⁻¹' s) * (κ a) (g ⁻¹' t)
u : Set α
s : Set β
t : Set γ
hu : MeasurableSet u
hs : MeasurableSet s
ht : MeasurableSet t
h_set_eq : ∀ (ω : α), Prod.mk ω ⁻¹' u ×ˢ s ×ˢ t = if ω ∈ u then s ×ˢ t else ∅
ω : α
hω : (κ ω) (f ⁻¹' s ∩ g ⁻¹' t) = (κ ω) (f ⁻¹' s) * (κ ω) (g ⁻¹' t)
hωu : ω ∉ u
⊢ ((κ.map fun ω ↦ (f ω, g ω)) ω) (if ω ∈ u then s ×ˢ t else ∅) = ((κ.map f ×ₖ κ.map g) ω) (if ω ∈ u then s ×ˢ t else ∅)

case pos
α : Type u_1
Ω : Type u_2
β : Type u_4
γ : Type u_6
mα : MeasurableSpace α
mΩ : MeasurableSpace Ω
κ : Kernel α Ω
μ : Measure α
mβ : MeasurableSpace β
mγ : MeasurableSpace γ
inst✝¹ : IsFiniteMeasure μ
inst✝ : IsFiniteKernel κ
f : Ω → β
g : Ω → γ
hf : Measurable f
hg : Measurable g
h :
  ∀ (s : Set β) (t : Set γ),
    MeasurableSet s → MeasurableSet t → ∀ᵐ (a : α) ∂μ, (κ a) (f ⁻¹' s ∩ g ⁻¹' t) = (κ a) (f ⁻¹' s) * (κ a) (g ⁻¹' t)
u : Set α
s : Set β
t : Set γ
hu : MeasurableSet u
hs : MeasurableSet s
ht : MeasurableSet t
h_set_eq : ∀ (ω : α), Prod.mk ω ⁻¹' u ×ˢ s ×ˢ t = if ω ∈ u then s ×ˢ t else ∅
ω : α
hω : (κ ω) (f ⁻¹' s ∩ g ⁻¹' t) = (κ ω) (f ⁻¹' s) * (κ ω) (g ⁻¹' t)
hωu : ω ∈ u
⊢ ((κ.map fun ω ↦ (f ω, g ω)) ω) (if ω ∈ u then s ×ˢ t else ∅) = ((κ.map f ×ₖ κ.map g) ω) (if ω ∈ u then s ×ˢ t else ∅)