mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.Probability.Distributions.Gaussian.HasGaussianLaw.Independence

Goal state before:
pp: Ω : Type u_1
mΩ : MeasurableSpace Ω
P : Measure Ω
E : Type u_2
inst✝⁴ : NormedAddCommGroup E
inst✝³ : NormedSpace ℝ E
inst✝² : MeasurableSpace E
inst✝¹ : BorelSpace E
inst✝ : SecondCountableTopology E
X Y : Ω → E
hX : HasGaussianLaw X P
hY : HasGaussianLaw Y P
h : X ⟂ᵢ[P] Y - X
this : IsProbabilityMeasure P
⊢ ∀ (L : StrongDual ℝ E),
    charFunDual (Measure.map (Y - X) P) L = cexp (↑(∫ (x : Ω), (⇑L ∘ (Y - X)) x ∂P) * I - ↑Var[⇑L ∘ (Y - X); P] / 2)

Tactic:
intro L

Goal state after:
Ω : Type u_1
mΩ : MeasurableSpace Ω
P : Measure Ω
E : Type u_2
inst✝⁴ : NormedAddCommGroup E
inst✝³ : NormedSpace ℝ E
inst✝² : MeasurableSpace E
inst✝¹ : BorelSpace E
inst✝ : SecondCountableTopology E
X Y : Ω → E
hX : HasGaussianLaw X P
hY : HasGaussianLaw Y P
h : X ⟂ᵢ[P] Y - X
this : IsProbabilityMeasure P
L : StrongDual ℝ E
⊢ charFunDual (Measure.map (Y - X) P) L = cexp (↑(∫ (x : Ω), (⇑L ∘ (Y - X)) x ∂P) * I - ↑Var[⇑L ∘ (Y - X); P] / 2)
Module: Mathlib.Probability.Kernel.Disintegration.StandardBorel

Goal state before:
pp: α : Type u_1
β : Type u_2
Ω : Type u_4
mα : MeasurableSpace α
mβ : MeasurableSpace β
mΩ : MeasurableSpace Ω
inst✝³ : StandardBorelSpace Ω
inst✝² : Nonempty Ω
κ : Kernel α (β × Ω)
inst✝¹ : IsSFiniteKernel κ
η : Kernel (α × β) ℝ
inst✝ : IsSFiniteKernel η
hη : (κ.map (Prod.map id (embeddingReal Ω))).fst ⊗ₖ η = κ.map (Prod.map id (embeddingReal Ω))
e : Ω → ℝ := embeddingReal Ω
he : MeasurableEmbedding (embeddingReal Ω) := measurableEmbedding_embeddingReal Ω
κ' : Kernel α (β × ℝ) := κ.map (Prod.map id e)
hη' : κ'.fst ⊗ₖ η = κ'
h_prod_embed : MeasurableEmbedding (Prod.map id e)
h_fst : κ'.fst = κ.fst
a : α
t : Set (β × Ω)
ht : MeasurableSet t
⊢ ((κ.fst ⊗ₖ borelMarkovFromReal Ω η) a) t = ((κ.fst ⊗ₖ η.comapRight he) a) t

Tactic:
compProd_apply ht

Goal state after:
α : Type u_1
β : Type u_2
Ω : Type u_4
mα : MeasurableSpace α
mβ : MeasurableSpace β
mΩ : MeasurableSpace Ω
inst✝³ : StandardBorelSpace Ω
inst✝² : Nonempty Ω
κ : Kernel α (β × Ω)
inst✝¹ : IsSFiniteKernel κ
η : Kernel (α × β) ℝ
inst✝ : IsSFiniteKernel η
hη : (κ.map (Prod.map id (embeddingReal Ω))).fst ⊗ₖ η = κ.map (Prod.map id (embeddingReal Ω))
e : Ω → ℝ := embeddingReal Ω
he : MeasurableEmbedding (embeddingReal Ω) := measurableEmbedding_embeddingReal Ω
κ' : Kernel α (β × ℝ) := κ.map (Prod.map id e)
hη' : κ'.fst ⊗ₖ η = κ'
h_prod_embed : MeasurableEmbedding (Prod.map id e)
h_fst : κ'.fst = κ.fst
a : α
t : Set (β × Ω)
ht : MeasurableSet t
⊢ ∫⁻ (b : β), ((borelMarkovFromReal Ω η) (a, b)) (Prod.mk b ⁻¹' t) ∂κ.fst a =
    ∫⁻ (b : β), ((η.comapRight he) (a, b)) (Prod.mk b ⁻¹' t) ∂κ.fst a
Module: Mathlib.Probability.Kernel.IonescuTulcea.Maps

Goal state before:
pp: ι : Type u_1
inst✝³ : LinearOrder ι
inst✝² : LocallyFiniteOrder ι
inst✝¹ : DecidableLE ι
X : ι → Type u_2
inst✝ : LocallyFiniteOrderBot ι
a b : ι
hab : a ≤ b
⊢ frestrictLe₂ hab ∘ IicProdIoc a b = Prod.fst

Tactic:
ext x i
  simp [IicProdIoc, mem_Iic.1 i.2]

Goal state after:
Module: Mathlib.Probability.Kernel.IonescuTulcea.Maps

Goal state before:
pp: ι : Type u_1
inst✝³ : LinearOrder ι
inst✝² : LocallyFiniteOrder ι
inst✝¹ : DecidableLE ι
X : ι → Type u_2
inst✝ : LocallyFiniteOrderBot ι
a : ι
⊢ IicProdIoc a a = Prod.fst

Tactic:
ext x i
  simp [IicProdIoc, mem_Iic.1 i.2]

Goal state after:
Module: Mathlib.Probability.Kernel.Integral

Goal state before:
pp: α : Type u_1
β : Type u_2
mα : MeasurableSpace α
mβ : MeasurableSpace β
κ : Kernel α β
E : Type u_3
inst✝¹ : NormedAddCommGroup E
inst✝ : NormedSpace ℝ E
f g : α → β → E
μ : Measure α
h : ∀ᵐ (a : α) ∂μ, f a =ᵐ[κ a] g a
⊢ (fun a ↦ ∫ (b : β), f a b ∂κ a) =ᵐ[μ] fun a ↦ ∫ (b : β), g a b ∂κ a

Tactic:
filter_upwards [h] with _ ha

Goal state after:
α : Type u_1
β : Type u_2
mα : MeasurableSpace α
mβ : MeasurableSpace β
κ : Kernel α β
E : Type u_3
inst✝¹ : NormedAddCommGroup E
inst✝ : NormedSpace ℝ E
f g : α → β → E
μ : Measure α
h : ∀ᵐ (a : α) ∂μ, f a =ᵐ[κ a] g a
a✝ : α
ha : f a✝ =ᵐ[κ a✝] g a✝
⊢ ∫ (b : β), f a✝ b ∂κ a✝ = ∫ (b : β), g a✝ b ∂κ a✝
Module: Mathlib.Probability.Kernel.CondDistrib

Goal state before:
pp: case refine_2
α : Type u_1
β : Type u_2
Ω : Type u_3
F : Type u_4
inst✝⁶ : MeasurableSpace Ω
inst✝⁵ : StandardBorelSpace Ω
inst✝⁴ : Nonempty Ω
inst✝³ : NormedAddCommGroup F
mα : MeasurableSpace α
μ : Measure α
inst✝² : IsFiniteMeasure μ
X : α → β
Y : α → Ω
mβ : MeasurableSpace β
f : β × Ω → F
inst✝¹ : NormedSpace ℝ F
inst✝ : CompleteSpace F
hX : Measurable X
hY : AEMeasurable Y μ
hf_int : Integrable f (Measure.map (fun a ↦ (X a, Y a)) μ)
hf_int' : Integrable (fun a ↦ f (X a, Y a)) μ
t : Set β
ht : MeasurableSet t
a✝ : μ (X ⁻¹' t) < ∞
⊢ ∫ (x : α) in X ⁻¹' t, ∫ (y : Ω), f (X x, y) ∂(condDistrib Y X μ) (X x) ∂μ = ∫ (x : α) in X ⁻¹' t, f (X x, Y x) ∂μ

Tactic:
change ∫ a in X ⁻¹' t, ((fun x' => ∫ y, f (x', y) ∂(condDistrib Y X μ) x') ∘ X) a ∂μ =
      ∫ a in X ⁻¹' t, f (X a, Y a) ∂μ

Goal state after:
case refine_2
α : Type u_1
β : Type u_2
Ω : Type u_3
F : Type u_4
inst✝⁶ : MeasurableSpace Ω
inst✝⁵ : StandardBorelSpace Ω
inst✝⁴ : Nonempty Ω
inst✝³ : NormedAddCommGroup F
mα : MeasurableSpace α
μ : Measure α
inst✝² : IsFiniteMeasure μ
X : α → β
Y : α → Ω
mβ : MeasurableSpace β
f : β × Ω → F
inst✝¹ : NormedSpace ℝ F
inst✝ : CompleteSpace F
hX : Measurable X
hY : AEMeasurable Y μ
hf_int : Integrable f (Measure.map (fun a ↦ (X a, Y a)) μ)
hf_int' : Integrable (fun a ↦ f (X a, Y a)) μ
t : Set β
ht : MeasurableSet t
a✝ : μ (X ⁻¹' t) < ∞
⊢ ∫ (a : α) in X ⁻¹' t, ((fun x' ↦ ∫ (y : Ω), f (x', y) ∂(condDistrib Y X μ) x') ∘ X) a ∂μ =
    ∫ (a : α) in X ⁻¹' t, f (X a, Y a) ∂μ
Module: Mathlib.Probability.Kernel.Disintegration.Density

Goal state before:
pp: case hs
α : Type u_1
β : Type u_2
γ : Type u_3
mα : MeasurableSpace α
mβ : MeasurableSpace β
mγ : MeasurableSpace γ
inst✝¹ : CountablyGenerated γ
κ : Kernel α (γ × β)
inst✝ : IsFiniteKernel κ
n : ℕ
a : α
this✝ : {x | ¬κ.densityProcess κ.fst n a x univ = 1} ⊆ {x | (κ.fst a) (countablePartitionSet n x) = 0}
this : {x | (κ.fst a) (countablePartitionSet n x) = 0} ⊆ ⋃ u ∈ countablePartition γ n, ⋃ (_ : (κ.fst a) u = 0), u
⊢ (countablePartition γ n).Countable

pp: case hd
α : Type u_1
β : Type u_2
γ : Type u_3
mα : MeasurableSpace α
mβ : MeasurableSpace β
mγ : MeasurableSpace γ
inst✝¹ : CountablyGenerated γ
κ : Kernel α (γ × β)
inst✝ : IsFiniteKernel κ
n : ℕ
a : α
this✝ : {x | ¬κ.densityProcess κ.fst n a x univ = 1} ⊆ {x | (κ.fst a) (countablePartitionSet n x) = 0}
this : {x | (κ.fst a) (countablePartitionSet n x) = 0} ⊆ ⋃ u ∈ countablePartition γ n, ⋃ (_ : (κ.fst a) u = 0), u
⊢ (countablePartition γ n).PairwiseDisjoint fun u ↦ ⋃ (_ : (κ.fst a) u = 0), u

pp: case h
α : Type u_1
β : Type u_2
γ : Type u_3
mα : MeasurableSpace α
mβ : MeasurableSpace β
mγ : MeasurableSpace γ
inst✝¹ : CountablyGenerated γ
κ : Kernel α (γ × β)
inst✝ : IsFiniteKernel κ
n : ℕ
a : α
this✝ : {x | ¬κ.densityProcess κ.fst n a x univ = 1} ⊆ {x | (κ.fst a) (countablePartitionSet n x) = 0}
this : {x | (κ.fst a) (countablePartitionSet n x) = 0} ⊆ ⋃ u ∈ countablePartition γ n, ⋃ (_ : (κ.fst a) u = 0), u
⊢ ∀ b ∈ countablePartition γ n, MeasurableSet (⋃ (_ : (κ.fst a) b = 0), b)

Tactic:
· exact (finite_countablePartition _ _).countable

Goal state after:
case hd
α : Type u_1
β : Type u_2
γ : Type u_3
mα : MeasurableSpace α
mβ : MeasurableSpace β
mγ : MeasurableSpace γ
inst✝¹ : CountablyGenerated γ
κ : Kernel α (γ × β)
inst✝ : IsFiniteKernel κ
n : ℕ
a : α
this✝ : {x | ¬κ.densityProcess κ.fst n a x univ = 1} ⊆ {x | (κ.fst a) (countablePartitionSet n x) = 0}
this : {x | (κ.fst a) (countablePartitionSet n x) = 0} ⊆ ⋃ u ∈ countablePartition γ n, ⋃ (_ : (κ.fst a) u = 0), u
⊢ (countablePartition γ n).PairwiseDisjoint fun u ↦ ⋃ (_ : (κ.fst a) u = 0), u

case h
α : Type u_1
β : Type u_2
γ : Type u_3
mα : MeasurableSpace α
mβ : MeasurableSpace β
mγ : MeasurableSpace γ
inst✝¹ : CountablyGenerated γ
κ : Kernel α (γ × β)
inst✝ : IsFiniteKernel κ
n : ℕ
a : α
this✝ : {x | ¬κ.densityProcess κ.fst n a x univ = 1} ⊆ {x | (κ.fst a) (countablePartitionSet n x) = 0}
this : {x | (κ.fst a) (countablePartitionSet n x) = 0} ⊆ ⋃ u ∈ countablePartition γ n, ⋃ (_ : (κ.fst a) u = 0), u
⊢ ∀ b ∈ countablePartition γ n, MeasurableSet (⋃ (_ : (κ.fst a) b = 0), b)
Module: Mathlib.Probability.Kernel.Disintegration.Density

Goal state before:
pp: α : Type u_1
β : Type u_2
γ : Type u_3
mα : MeasurableSpace α
mβ : MeasurableSpace β
mγ : MeasurableSpace γ
inst✝ : CountablyGenerated γ
κ : Kernel α (γ × β)
n : ℕ
a : α
x : γ
seq : ℕ → Set β
hseq : Monotone seq
hseq_iUnion : ⋃ i, seq i = univ
h0 : (κ a) {p | p.1 ∈ countablePartitionSet n x} = 0
this✝ : ∀ (m : ℕ), (κ a) (countablePartitionSet n x ×ˢ seq m) = 0
this : (κ a) (countablePartitionSet n x ×ˢ univ) = 0
⊢ 0 = (κ a) (countablePartitionSet n x ×ˢ univ) / 0

Tactic:
simp only [this, ENNReal.zero_div]

Goal state after:
Module: Mathlib.Probability.Kernel.Disintegration.Density

Goal state before:
pp: α : Type u_1
β : Type u_2
γ : Type u_3
mα : MeasurableSpace α
mβ : MeasurableSpace β
mγ : MeasurableSpace γ
inst✝¹ : CountablyGenerated γ
κ : Kernel α (γ × β)
inst✝ : IsFiniteKernel κ
a : α
seq : ℕ → Set β
hseq : Monotone seq
hseq_iUnion : ⋃ i, seq i = univ
hseq_meas : ∀ (m : ℕ), MeasurableSet (seq m)
⊢ (κ.fst a).real univ = (κ a).real univ

Tactic:
simp only [measureReal_def]

Goal state after:
α : Type u_1
β : Type u_2
γ : Type u_3
mα : MeasurableSpace α
mβ : MeasurableSpace β
mγ : MeasurableSpace γ
inst✝¹ : CountablyGenerated γ
κ : Kernel α (γ × β)
inst✝ : IsFiniteKernel κ
a : α
seq : ℕ → Set β
hseq : Monotone seq
hseq_iUnion : ⋃ i, seq i = univ
hseq_meas : ∀ (m : ℕ), MeasurableSet (seq m)
⊢ ((κ.fst a) univ).toReal = ((κ a) univ).toReal
Module: Mathlib.Probability.Kernel.WithDensity

Goal state before:
pp: case neg
α : Type u_1
β : Type u_2
mα : MeasurableSpace α
mβ : MeasurableSpace β
κ : Kernel α β
inst✝ : IsSFiniteKernel κ
f : α → β → ℝ≥0∞
a : α
hf : ¬Measurable (Function.uncurry f)
⊢ (κ.withDensity f) a ≪ κ a

Tactic:
withDensity_of_not_measurable _ hf

Goal state after:
case neg
α : Type u_1
β : Type u_2
mα : MeasurableSpace α
mβ : MeasurableSpace β
κ : Kernel α β
inst✝ : IsSFiniteKernel κ
f : α → β → ℝ≥0∞
a : α
hf : ¬Measurable (Function.uncurry f)
⊢ 0 a ≪ κ a
Module: Mathlib.Probability.Kernel.WithDensity

Goal state before:
pp: case neg
α : Type u_1
β : Type u_2
mα : MeasurableSpace α
mβ : MeasurableSpace β
κ η : Kernel α β
inst✝¹ : IsSFiniteKernel κ
inst✝ : IsSFiniteKernel η
f : α → β → ℝ≥0∞
hf : ¬Measurable (Function.uncurry f)
⊢ (κ + η).withDensity f = κ.withDensity f + η.withDensity f

Tactic:
withDensity_of_not_measurable _ hf

Goal state after:
case neg
α : Type u_1
β : Type u_2
mα : MeasurableSpace α
mβ : MeasurableSpace β
κ η : Kernel α β
inst✝¹ : IsSFiniteKernel κ
inst✝ : IsSFiniteKernel η
f : α → β → ℝ≥0∞
hf : ¬Measurable (Function.uncurry f)
⊢ 0 = 0 + 0
Module: Mathlib.Probability.Kernel.WithDensity

Goal state before:
pp: case neg
α : Type u_1
β : Type u_2
ι : Type u_3
mα : MeasurableSpace α
mβ : MeasurableSpace β
inst✝ : Countable ι
κ : ι → Kernel α β
hκ : ∀ (i : ι), IsSFiniteKernel (κ i)
f : α → β → ℝ≥0∞
hf : ¬Measurable (Function.uncurry f)
⊢ (Kernel.sum κ).withDensity f = Kernel.sum fun i ↦ (κ i).withDensity f

Tactic:
withDensity_of_not_measurable _ hf

Goal state after:
case neg
α : Type u_1
β : Type u_2
ι : Type u_3
mα : MeasurableSpace α
mβ : MeasurableSpace β
inst✝ : Countable ι
κ : ι → Kernel α β
hκ : ∀ (i : ι), IsSFiniteKernel (κ i)
f : α → β → ℝ≥0∞
hf : ¬Measurable (Function.uncurry f)
⊢ 0 = Kernel.sum fun i ↦ 0
Module: Mathlib.Probability.Kernel.WithDensity

Goal state before:
pp: case neg
α : Type u_1
β : Type u_2
mα : MeasurableSpace α
mβ : MeasurableSpace β
f : α → β → ℝ≥0∞
κ : Kernel α β
inst✝ : IsFiniteKernel κ
B : ℝ≥0∞
hB_top : B ≠ ∞
hf_B : ∀ (a : α) (b : β), f a b ≤ B
hf : ¬Measurable (Function.uncurry f)
⊢ IsFiniteKernel (κ.withDensity f)

Tactic:
withDensity_of_not_measurable _ hf

Goal state after:
case neg
α : Type u_1
β : Type u_2
mα : MeasurableSpace α
mβ : MeasurableSpace β
f : α → β → ℝ≥0∞
κ : Kernel α β
inst✝ : IsFiniteKernel κ
B : ℝ≥0∞
hB_top : B ≠ ∞
hf_B : ∀ (a : α) (b : β), f a b ≤ B
hf : ¬Measurable (Function.uncurry f)
⊢ IsFiniteKernel 0
Module: Mathlib.Probability.Kernel.WithDensity

Goal state before:
pp: case neg
α : Type u_1
β : Type u_2
mα : MeasurableSpace α
mβ : MeasurableSpace β
f : α → β → ℝ≥0∞
κ : Kernel α β
inst✝ : IsFiniteKernel κ
hf_ne_top : ∀ (a : α) (b : β), f a b ≠ ∞
hf : ¬Measurable (Function.uncurry f)
⊢ IsSFiniteKernel (κ.withDensity f)

Tactic:
withDensity_of_not_measurable _ hf

Goal state after:
case neg
α : Type u_1
β : Type u_2
mα : MeasurableSpace α
mβ : MeasurableSpace β
f : α → β → ℝ≥0∞
κ : Kernel α β
inst✝ : IsFiniteKernel κ
hf_ne_top : ∀ (a : α) (b : β), f a b ≠ ∞
hf : ¬Measurable (Function.uncurry f)
⊢ IsSFiniteKernel 0
Module: Mathlib.Probability.Kernel.IonescuTulcea.Traj

Goal state before:
pp: X : ℕ → Type u_1
inst✝¹ : (n : ℕ) → MeasurableSpace (X n)
κ : (n : ℕ) → Kernel ((i : ↥(Iic n)) → X ↑i) (X (n + 1))
inst✝ : ∀ (n : ℕ), IsMarkovKernel (κ n)
A : ℕ → Set ((n : ℕ) → X n)
A_mem : ∀ (n : ℕ), A n ∈ measurableCylinders X
A_anti : Antitone A
A_inter : ⋂ n, A n = ∅
p : ℕ
x₀ : (i : ↥(Iic p)) → X ↑i
x✝ : ∀ (n : ℕ), Nonempty (X n)
a : ℕ → ℕ
S : (n : ℕ) → Set ((i : ↥(Iic (a n))) → X ↑i)
mS : ∀ (n : ℕ), MeasurableSet (S n)
A_eq : ∀ (n : ℕ), A n = cylinder (Iic (a n)) (S n)
χ : ℕ → ((n : ℕ) → X n) → ℝ≥0∞ := fun n ↦ (A n).indicator 1
mχ : ∀ (n : ℕ), Measurable (χ n)
χ_dep : ∀ (n : ℕ), DependsOn (χ n) ↑(Iic (a n))
lma_const :
  ∀ (x y : (i : ℕ) → X i) (n : ℕ),
    lmarginalPartialTraj κ p (a n) (χ n) (updateFinset x (Iic p) x₀) =
      lmarginalPartialTraj κ p (a n) (χ n) (updateFinset y (Iic p) x₀)
χ_anti : Antitone χ
lma_inv : ∀ (k M n : ℕ), a n ≤ M → lmarginalPartialTraj κ k M (χ n) = lmarginalPartialTraj κ k (a n) (χ n)
anti_lma : ∀ (k : ℕ) (x : (n : ℕ) → X n), Antitone fun n ↦ lmarginalPartialTraj κ k (a n) (χ n) x
l : ℕ → ((n : ℕ) → X n) → ℝ≥0∞
hl : ∀ (k : ℕ) (x : (n : ℕ) → X n), Tendsto (fun n ↦ lmarginalPartialTraj κ k (a n) (χ n) x) atTop (𝓝 (l k x))
⊢ Tendsto (fun n ↦ (trajContent κ x₀) (A n)) atTop (𝓝 0)

Tactic:
have l_const x y : l p (updateFinset x _ x₀) = l p (updateFinset y _ x₀) := by
    have := hl p (updateFinset x _ x₀)
    simp_rw [lma_const x y] at this
    exact tendsto_nhds_unique this (hl p _)

Goal state after:
X : ℕ → Type u_1
inst✝¹ : (n : ℕ) → MeasurableSpace (X n)
κ : (n : ℕ) → Kernel ((i : ↥(Iic n)) → X ↑i) (X (n + 1))
inst✝ : ∀ (n : ℕ), IsMarkovKernel (κ n)
A : ℕ → Set ((n : ℕ) → X n)
A_mem : ∀ (n : ℕ), A n ∈ measurableCylinders X
A_anti : Antitone A
A_inter : ⋂ n, A n = ∅
p : ℕ
x₀ : (i : ↥(Iic p)) → X ↑i
x✝ : ∀ (n : ℕ), Nonempty (X n)
a : ℕ → ℕ
S : (n : ℕ) → Set ((i : ↥(Iic (a n))) → X ↑i)
mS : ∀ (n : ℕ), MeasurableSet (S n)
A_eq : ∀ (n : ℕ), A n = cylinder (Iic (a n)) (S n)
χ : ℕ → ((n : ℕ) → X n) → ℝ≥0∞ := fun n ↦ (A n).indicator 1
mχ : ∀ (n : ℕ), Measurable (χ n)
χ_dep : ∀ (n : ℕ), DependsOn (χ n) ↑(Iic (a n))
lma_const :
  ∀ (x y : (i : ℕ) → X i) (n : ℕ),
    lmarginalPartialTraj κ p (a n) (χ n) (updateFinset x (Iic p) x₀) =
      lmarginalPartialTraj κ p (a n) (χ n) (updateFinset y (Iic p) x₀)
χ_anti : Antitone χ
lma_inv : ∀ (k M n : ℕ), a n ≤ M → lmarginalPartialTraj κ k M (χ n) = lmarginalPartialTraj κ k (a n) (χ n)
anti_lma : ∀ (k : ℕ) (x : (n : ℕ) → X n), Antitone fun n ↦ lmarginalPartialTraj κ k (a n) (χ n) x
l : ℕ → ((n : ℕ) → X n) → ℝ≥0∞
hl : ∀ (k : ℕ) (x : (n : ℕ) → X n), Tendsto (fun n ↦ lmarginalPartialTraj κ k (a n) (χ n) x) atTop (𝓝 (l k x))
l_const : ∀ (x y : (i : ℕ) → X i), l p (updateFinset x (Iic p) x₀) = l p (updateFinset y (Iic p) x₀)
⊢ Tendsto (fun n ↦ (trajContent κ x₀) (A n)) atTop (𝓝 0)
Module: Mathlib.Probability.Kernel.IonescuTulcea.Traj

Goal state before:
pp: X : ℕ → Type u_1
inst✝¹ : (n : ℕ) → MeasurableSpace (X n)
κ : (n : ℕ) → Kernel ((i : ↥(Iic n)) → X ↑i) (X (n + 1))
inst✝ : ∀ (n : ℕ), IsMarkovKernel (κ n)
A : ℕ → Set ((n : ℕ) → X n)
A_mem : ∀ (n : ℕ), A n ∈ measurableCylinders X
A_anti : Antitone A
A_inter : ⋂ n, A n = ∅
p : ℕ
x₀ : (i : ↥(Iic p)) → X ↑i
x✝ : ∀ (n : ℕ), Nonempty (X n)
a : ℕ → ℕ
S : (n : ℕ) → Set ((i : ↥(Iic (a n))) → X ↑i)
mS : ∀ (n : ℕ), MeasurableSet (S n)
A_eq : ∀ (n : ℕ), A n = cylinder (Iic (a n)) (S n)
χ : ℕ → ((n : ℕ) → X n) → ℝ≥0∞ := fun n ↦ (A n).indicator 1
mχ : ∀ (n : ℕ), Measurable (χ n)
χ_dep : ∀ (n : ℕ), DependsOn (χ n) ↑(Iic (a n))
lma_const :
  ∀ (x y : (i : ℕ) → X i) (n : ℕ),
    lmarginalPartialTraj κ p (a n) (χ n) (updateFinset x (Iic p) x₀) =
      lmarginalPartialTraj κ p (a n) (χ n) (updateFinset y (Iic p) x₀)
χ_anti : Antitone χ
lma_inv : ∀ (k M n : ℕ), a n ≤ M → lmarginalPartialTraj κ k M (χ n) = lmarginalPartialTraj κ k (a n) (χ n)
anti_lma : ∀ (k : ℕ) (x : (n : ℕ) → X n), Antitone fun n ↦ lmarginalPartialTraj κ k (a n) (χ n) x
l : ℕ → ((n : ℕ) → X n) → ℝ≥0∞
hl : ∀ (k : ℕ) (x : (n : ℕ) → X n), Tendsto (fun n ↦ lmarginalPartialTraj κ k (a n) (χ n) x) atTop (𝓝 (l k x))
l_const : ∀ (x y : (i : ℕ) → X i), l p (updateFinset x (Iic p) x₀) = l p (updateFinset y (Iic p) x₀)
ε : ℝ≥0∞
hε : ∀ (x : (i : ℕ) → X i), l p (updateFinset x (Iic p) x₀) = ε
⊢ Tendsto (fun n ↦ (trajContent κ x₀) (A n)) atTop (𝓝 0)

Tactic:
have hpos x n : ε ≤ lmarginalPartialTraj κ p (a n) (χ n) (updateFinset x _ x₀) :=
    hε x ▸ ((anti_lma p _).le_of_tendsto (hl p _)) n

Goal state after:
X : ℕ → Type u_1
inst✝¹ : (n : ℕ) → MeasurableSpace (X n)
κ : (n : ℕ) → Kernel ((i : ↥(Iic n)) → X ↑i) (X (n + 1))
inst✝ : ∀ (n : ℕ), IsMarkovKernel (κ n)
A : ℕ → Set ((n : ℕ) → X n)
A_mem : ∀ (n : ℕ), A n ∈ measurableCylinders X
A_anti : Antitone A
A_inter : ⋂ n, A n = ∅
p : ℕ
x₀ : (i : ↥(Iic p)) → X ↑i
x✝ : ∀ (n : ℕ), Nonempty (X n)
a : ℕ → ℕ
S : (n : ℕ) → Set ((i : ↥(Iic (a n))) → X ↑i)
mS : ∀ (n : ℕ), MeasurableSet (S n)
A_eq : ∀ (n : ℕ), A n = cylinder (Iic (a n)) (S n)
χ : ℕ → ((n : ℕ) → X n) → ℝ≥0∞ := fun n ↦ (A n).indicator 1
mχ : ∀ (n : ℕ), Measurable (χ n)
χ_dep : ∀ (n : ℕ), DependsOn (χ n) ↑(Iic (a n))
lma_const :
  ∀ (x y : (i : ℕ) → X i) (n : ℕ),
    lmarginalPartialTraj κ p (a n) (χ n) (updateFinset x (Iic p) x₀) =
      lmarginalPartialTraj κ p (a n) (χ n) (updateFinset y (Iic p) x₀)
χ_anti : Antitone χ
lma_inv : ∀ (k M n : ℕ), a n ≤ M → lmarginalPartialTraj κ k M (χ n) = lmarginalPartialTraj κ k (a n) (χ n)
anti_lma : ∀ (k : ℕ) (x : (n : ℕ) → X n), Antitone fun n ↦ lmarginalPartialTraj κ k (a n) (χ n) x
l : ℕ → ((n : ℕ) → X n) → ℝ≥0∞
hl : ∀ (k : ℕ) (x : (n : ℕ) → X n), Tendsto (fun n ↦ lmarginalPartialTraj κ k (a n) (χ n) x) atTop (𝓝 (l k x))
l_const : ∀ (x y : (i : ℕ) → X i), l p (updateFinset x (Iic p) x₀) = l p (updateFinset y (Iic p) x₀)
ε : ℝ≥0∞
hε : ∀ (x : (i : ℕ) → X i), l p (updateFinset x (Iic p) x₀) = ε
hpos : ∀ (x : (i : ℕ) → X i) (n : ℕ), ε ≤ lmarginalPartialTraj κ p (a n) (χ n) (updateFinset x (Iic p) x₀)
⊢ Tendsto (fun n ↦ (trajContent κ x₀) (A n)) atTop (𝓝 0)
Module: Mathlib.Probability.Kernel.RadonNikodym

Goal state before:
pp: α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
κ η ξ : Kernel α γ
f : α → γ → ℝ≥0∞
inst✝ : IsFiniteKernel η
h : κ = η.withDensity f + ξ
hf : Measurable (Function.uncurry f)
a : α
hξ : ξ a ⟂ₘ η a
this : κ a = ξ a + (η a).withDensity (f a)
⊢ f a =ᵐ[η a] ∂κ a/∂η a

Tactic:
exact (κ a).eq_rnDeriv₀ (hf.comp measurable_prodMk_left).aemeasurable hξ this

Goal state after:
Module: Mathlib.Probability.ProductMeasure

Goal state before:
pp: ι : Type u_1
X : ι → Type u_2
mX : (i : ι) → MeasurableSpace (X i)
μ : (i : ι) → Measure (X i)
hμ : ∀ (i : ι), IsProbabilityMeasure (μ i)
I : Finset ι
s : Set ((i : ↥I) → X ↑i)
hs : MeasurableSet s
⊢ (piContent μ) (cylinder I s) = ((fun I ↦ Measure.pi fun i ↦ μ ↑i) I) s

pp: case hC_gen
ι : Type u_1
X : ι → Type u_2
mX : (i : ι) → MeasurableSpace (X i)
μ : (i : ι) → Measure (X i)
hμ : ∀ (i : ι), IsProbabilityMeasure (μ i)
I : Finset ι
s : Set ((i : ↥I) → X ↑i)
hs : MeasurableSet s
⊢ MeasurableSpace.pi = MeasurableSpace.generateFrom (measurableCylinders X)

pp: case hs
ι : Type u_1
X : ι → Type u_2
mX : (i : ι) → MeasurableSpace (X i)
μ : (i : ι) → Measure (X i)
hμ : ∀ (i : ι), IsProbabilityMeasure (μ i)
I : Finset ι
s : Set ((i : ↥I) → X ↑i)
hs : MeasurableSet s
⊢ I.restrict ⁻¹' s ∈ measurableCylinders X

Tactic:
piContent_cylinder μ hs

Goal state after:
ι : Type u_1
X : ι → Type u_2
mX : (i : ι) → MeasurableSpace (X i)
μ : (i : ι) → Measure (X i)
hμ : ∀ (i : ι), IsProbabilityMeasure (μ i)
I : Finset ι
s : Set ((i : ↥I) → X ↑i)
hs : MeasurableSet s
⊢ (Measure.pi fun i ↦ μ ↑i) s = ((fun I ↦ Measure.pi fun i ↦ μ ↑i) I) s

case hC_gen
ι : Type u_1
X : ι → Type u_2
mX : (i : ι) → MeasurableSpace (X i)
μ : (i : ι) → Measure (X i)
hμ : ∀ (i : ι), IsProbabilityMeasure (μ i)
I : Finset ι
s : Set ((i : ↥I) → X ↑i)
hs : MeasurableSet s
⊢ MeasurableSpace.pi = MeasurableSpace.generateFrom (measurableCylinders X)

case hs
ι : Type u_1
X : ι → Type u_2
mX : (i : ι) → MeasurableSpace (X i)
μ : (i : ι) → Measure (X i)
hμ : ∀ (i : ι), IsProbabilityMeasure (μ i)
I : Finset ι
s : Set ((i : ↥I) → X ↑i)
hs : MeasurableSet s
⊢ I.restrict ⁻¹' s ∈ measurableCylinders X
Module: Mathlib.Probability.Kernel.IonescuTulcea.Traj

Goal state before:
pp: X : ℕ → Type u_1
inst✝¹ : (n : ℕ) → MeasurableSpace (X n)
κ : (n : ℕ) → Kernel ((i : ↥(Iic n)) → X ↑i) (X (n + 1))
inst✝ : ∀ (n : ℕ), IsMarkovKernel (κ n)
a : ℕ
x₀ : (i : ↥(Iic a)) → X ↑i
⊢ (trajContent κ x₀).IsSigmaSubadditive

Tactic:
by
  refine isSigmaSubadditive_of_addContent_iUnion_eq_tsum
    isSetRing_measurableCylinders (fun f hf hf_Union hf' ↦ ?_)
  refine addContent_iUnion_eq_sum_of_tendsto_zero isSetRing_measurableCylinders
    (trajContent κ x₀) (fun _ _ ↦ trajContent_ne_top) ?_ hf hf_Union hf'
  exact fun s hs anti_s inter_s ↦ trajContent_tendsto_zero hs anti_s inter_s x₀

Goal state after:
Module: Mathlib.Probability.ProductMeasure

Goal state before:
pp: ι : Type u_1
X : ι → Type u_2
mX : (i : ι) → MeasurableSpace (X i)
μ : (i : ι) → Measure (X i)
hμ : ∀ (i : ι), IsProbabilityMeasure (μ i)
Y : ι → Type u_3
inst✝ : (i : ι) → MeasurableSpace (Y i)
f : (i : ι) → X i → Y i
hf : ∀ (i : ι), Measurable (f i)
this : ∀ (i : ι), IsProbabilityMeasure (map (f i) (μ i))
s : Finset ι
t : (i : ι) → Set (Y i)
ht : ∀ (i : ι), MeasurableSet (t i)
⊢ (infinitePi μ) ((fun x i ↦ f i (x i)) ⁻¹' (↑s).pi fun x ↦ t x) = ∏ i ∈ s, (map (f i) (μ i)) (t i)

Tactic:
have : (fun (x : Π i, X i) i ↦ f i (x i)) ⁻¹' ((s : Set ι).pi t) =
      (s : Set ι).pi (fun i ↦ (f i) ⁻¹' (t i)) := by ext x; simp

Goal state after:
ι : Type u_1
X : ι → Type u_2
mX : (i : ι) → MeasurableSpace (X i)
μ : (i : ι) → Measure (X i)
hμ : ∀ (i : ι), IsProbabilityMeasure (μ i)
Y : ι → Type u_3
inst✝ : (i : ι) → MeasurableSpace (Y i)
f : (i : ι) → X i → Y i
hf : ∀ (i : ι), Measurable (f i)
this✝ : ∀ (i : ι), IsProbabilityMeasure (map (f i) (μ i))
s : Finset ι
t : (i : ι) → Set (Y i)
ht : ∀ (i : ι), MeasurableSet (t i)
this : (fun x i ↦ f i (x i)) ⁻¹' (↑s).pi t = (↑s).pi fun i ↦ f i ⁻¹' t i
⊢ (infinitePi μ) ((fun x i ↦ f i (x i)) ⁻¹' (↑s).pi fun x ↦ t x) = ∏ i ∈ s, (map (f i) (μ i)) (t i)
Module: Mathlib.Probability.Kernel.Posterior

Goal state before:
pp: Ω : Type u_1
𝓧 : Type u_2
mΩ : MeasurableSpace Ω
m𝓧 : MeasurableSpace 𝓧
κ : Kernel Ω 𝓧
μ : Measure Ω
inst✝⁴ : IsFiniteMeasure μ
inst✝³ : IsFiniteKernel κ
inst✝² : StandardBorelSpace Ω
inst✝¹ : Nonempty Ω
inst✝ : MeasurableSpace.CountableOrCountablyGenerated Ω 𝓧
h_ac : ∀ᵐ (b : 𝓧) ∂⇑κ ∘ₘ μ, (κ†μ) b ≪ μ
this : (⇑κ ∘ₘ μ) ⊗ₘ κ†μ ≪ (⇑κ ∘ₘ μ).prod μ
⊢ μ ⊗ₘ κ ≪ μ.prod (⇑κ ∘ₘ μ)

Tactic:
← swap_compProd_posterior,

Goal state after:
Ω : Type u_1
𝓧 : Type u_2
mΩ : MeasurableSpace Ω
m𝓧 : MeasurableSpace 𝓧
κ : Kernel Ω 𝓧
μ : Measure Ω
inst✝⁴ : IsFiniteMeasure μ
inst✝³ : IsFiniteKernel κ
inst✝² : StandardBorelSpace Ω
inst✝¹ : Nonempty Ω
inst✝ : MeasurableSpace.CountableOrCountablyGenerated Ω 𝓧
h_ac : ∀ᵐ (b : 𝓧) ∂⇑κ ∘ₘ μ, (κ†μ) b ≪ μ
this : (⇑κ ∘ₘ μ) ⊗ₘ κ†μ ≪ (⇑κ ∘ₘ μ).prod μ
⊢ ⇑(Kernel.swap 𝓧 Ω) ∘ₘ (⇑κ ∘ₘ μ) ⊗ₘ κ†μ ≪ μ.prod (⇑κ ∘ₘ μ)