mathlib-initiative/mathlib-tactics huggingface dataset:
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
hpos : ∀ (x : (i : ℕ) → X i) (n : ℕ), ε ≤ lmarginalPartialTraj κ p (a n) (χ n) (updateFinset x (Iic p) x₀)
χ_le : ∀ (n : ℕ) (x : (n : ℕ) → X n), χ n x ≤ 1
ind : (k : ℕ) → ((i : ↥(Iic k)) → X ↑i) → X (k + 1)
hind :
  ∀ (k : ℕ) (y : (i : ↥(Iic k)) → X ↑i),
    (∀ (x : (i : ℕ) → X i) (n : ℕ), ε ≤ lmarginalPartialTraj κ k (a n) (χ n) (updateFinset x (Iic k) y)) →
      ∀ (x : (i : ℕ) → X i) (n : ℕ),
        ε ≤ lmarginalPartialTraj κ (k + 1) (a n) (χ n) (update (updateFinset x (Iic k) y) (k + 1) (ind k y))
z : (n : ℕ) → X n := iterateInduction x₀ ind
k : ℕ
hk : p ≤ k
⊢ ∀ (x : (i : ℕ) → X i) (n : ℕ), ε ≤ lmarginalPartialTraj κ k (a n) (χ n) (updateFinset x (Iic k) (frestrictLe k z))

Tactic:
by

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

Goal state before:
pp: α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
κ η : Kernel α γ
inst✝¹ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
a : α
⊢ (η.withDensity (κ.rnDeriv η)) a = 0 ↔ κ a ⟂ₘ η a

Tactic:
by

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

Goal state before:
pp: α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
κ η : Kernel α γ
inst✝¹ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
a : α
⊢ (κ.singularPart η) a = 0 ↔ (κ a) (κ.mutuallySingularSetSlice η a) = 0

Tactic:
by

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

Goal state before:
pp: α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
κ η : Kernel α γ
inst✝¹ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
a : α
⊢ (η.withDensity (κ.rnDeriv η)) a = 0 ↔ (κ a) (κ.mutuallySingularSetSlice η a)ᶜ = 0

Tactic:
by

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

Goal state before:
pp: α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
κ η : Kernel α γ
inst✝¹ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
⊢ MeasurableSet {a | κ a ≪ η a}

Tactic:
by

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

Goal state before:
pp: α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
κ η : Kernel α γ
inst✝¹ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
⊢ MeasurableSet {a | κ a ⟂ₘ η a}

Tactic:
by

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

Goal state before:
pp: α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
κ : Kernel α γ
inst✝ : IsFiniteKernel κ
⊢ κ.singularPart κ = 0

Tactic:
ext : 1; rw [zero_apply, singularPart_eq_zero_iff_absolutelyContinuous]

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

Goal state before:
pp: α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
κ : Kernel α γ
inst✝ : IsFiniteKernel κ
⊢ κ.singularPart κ = 0

Tactic:
by

Goal state after:
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
⊢ κ a = ξ a + (η a).withDensity (f a)

Tactic:
by

Goal state after:
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
⊢ f a =ᵐ[η a] ∂κ a/∂η a

Tactic:
by

Goal state after:
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
⊢ ξ a = (κ a).singularPart (η a)

Tactic:
by

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

Goal state before:
pp: X : ℕ → Type u_1
mX : (n : ℕ) → MeasurableSpace (X n)
κ : (n : ℕ) → Kernel ((i : ↥(Iic n)) → X ↑i) (X (n + 1))
inst✝ : ∀ (n : ℕ), IsSFiniteKernel (κ n)
a : ℕ
f : ((n : ℕ) → X n) → ℝ≥0∞
mf : Measurable f
x₀ : (n : ℕ) → X n
⊢ lmarginalPartialTraj κ a (a + 1) f x₀ = ∫⁻ (x : X (a + 1)), f (update x₀ (a + 1) x) ∂(κ a) (frestrictLe a x₀)

Tactic:
by

Goal state after:
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 : Kernel α γ
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
hκ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
⊢ IsFiniteKernel (η.withDensity (κ.rnDeriv η))

Tactic:
by

Goal state after:
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 : Kernel α γ
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
hκ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
a : α
⊢ ((η.withDensity (κ.rnDeriv η)) a) univ + ((κ.singularPart η) a) univ = (κ a) univ

Tactic:
by

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

Goal state before:
pp: X : ℕ → Type u_1
mX : (n : ℕ) → MeasurableSpace (X n)
κ : (n : ℕ) → Kernel ((i : ↥(Iic n)) → X ↑i) (X (n + 1))
a b : ℕ
f : ((n : ℕ) → X n) → ℝ≥0∞
hf : Measurable f
⊢ Measurable (lmarginalPartialTraj κ a b f)

Tactic:
by

Goal state after:
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 : Kernel α γ
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
hκ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
⊢ IsFiniteKernel (κ.singularPart η)

Tactic:
by

Goal state after:
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
hpos : ∀ (x : (i : ℕ) → X i) (n : ℕ), ε ≤ lmarginalPartialTraj κ p (a n) (χ n) (updateFinset x (Iic p) x₀)
χ_le : ∀ (n : ℕ) (x : (n : ℕ) → X n), χ n x ≤ 1
ind : (k : ℕ) → ((i : ↥(Iic k)) → X ↑i) → X (k + 1)
hind :
  ∀ (k : ℕ) (y : (i : ↥(Iic k)) → X ↑i),
    (∀ (x : (i : ℕ) → X i) (n : ℕ), ε ≤ lmarginalPartialTraj κ k (a n) (χ n) (updateFinset x (Iic k) y)) →
      ∀ (x : (i : ℕ) → X i) (n : ℕ),
        ε ≤ lmarginalPartialTraj κ (k + 1) (a n) (χ n) (update (updateFinset x (Iic k) y) (k + 1) (ind k y))
z : (n : ℕ) → X n := iterateInduction x₀ ind
main :
  ∀ (k : ℕ),
    p ≤ k →
      ∀ (x : (i : ℕ) → X i) (n : ℕ), ε ≤ lmarginalPartialTraj κ k (a n) (χ n) (updateFinset x (Iic k) (frestrictLe k z))
x : (i : ℕ) → X i
n : ℕ
⊢ (trajContent κ x₀) (A n) = lmarginalPartialTraj κ p (a n) (χ n) (updateFinset x (Iic p) x₀)

Tactic:
by

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

Goal state before:
pp: α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
κ η : Kernel α γ
inst✝¹ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
⊢ Measurable fun a ↦ (κ a).singularPart (η a)

Tactic:
by

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

Goal state before:
pp: α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
κ ν : Kernel α γ
inst✝¹ : IsFiniteKernel κ
inst✝ : IsFiniteKernel ν
a : α
⊢ (κ.singularPart ν).rnDeriv ν a =ᵐ[ν a] 0

Tactic:
by

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

Goal state before:
pp: α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
κ η : Kernel α γ
inst✝¹ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
a : α
⊢ ∀ᵐ (x : γ) ∂η a, κ.rnDeriv η a x < ∞

Tactic:
by

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

Goal state before:
pp: α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
κ η : Kernel α γ
inst✝¹ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
a : α
⊢ ∀ᵐ (x : γ) ∂η a, κ.rnDeriv η a x ≠ ∞

Tactic:
by

Goal state after:
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 : Kernel α γ
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
inst✝¹ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
a : α
ha : κ a ≪ η a
⊢ ∀ᵐ (x : γ) ∂κ a, 0 < κ.rnDeriv η a x

Tactic:
by

Goal state after:
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 : Kernel α γ
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
inst✝¹ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
a : α
h : κ a ≪ η a
⊢ ∀ᵐ (x : γ) ∂κ a, 0 < (κ.rnDeriv η a x).toReal

Tactic:
by

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

Goal state before:
pp: α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
κ ν η : Kernel α γ
inst✝² : IsFiniteKernel κ
inst✝¹ : IsFiniteKernel ν
inst✝ : IsFiniteKernel η
a : α
⊢ (κ + ν).rnDeriv η a =ᵐ[η a] κ.rnDeriv η a + ν.rnDeriv η a

Tactic:
by

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

Goal state before:
pp: α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
κ η : Kernel α γ
inst✝¹ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
a : α
s : Set γ
hs : MeasurableSet s
⊢ ∫⁻ (c : γ) in s, κ.rnDeriv η a c ∂η a ≤ (κ a) s

Tactic:
by

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

Goal state before:
pp: α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
κ η : Kernel α γ
inst✝¹ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
a : α
h : κ a ≪ η a
s : Set γ
hs : MeasurableSet s
⊢ ∫⁻ (c : γ) in s, κ.rnDeriv η a c ∂η a = (κ a) s

Tactic:
by

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)
A : ℕ → Set ((i : ι) → X i)
A_mem : ∀ (n : ℕ), A n ∈ measurableCylinders X
A_anti : Antitone A
A_inter : ⋂ n, A n = ∅
⊢ Tendsto (fun n ↦ (piContent μ) (A n)) atTop (𝓝 0)

Tactic:
by

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

Goal state before:
pp: α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
κ η : Kernel α γ
inst✝¹ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
a : α
h : κ a ≪ η a
⊢ ∫⁻ (c : γ), κ.rnDeriv η a c ∂η a = (κ a) univ

Tactic:
by

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)
⊢ (piContent μ).IsSigmaSubadditive

Tactic:
by

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

Goal state before:
pp: α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
κ η : Kernel α γ
inst✝¹ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
a : α
⊢ (η.withDensity (κ.rnDeriv η)) a ≤ κ a

Tactic:
by

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

Goal state before:
pp: X : ℕ → Type u_1
mX : (n : ℕ) → MeasurableSpace (X n)
a b c : ℕ
κ : (n : ℕ) → Kernel ((i : ↥(Iic n)) → X ↑i) (X (n + 1))
hab : a ≤ b
hbc : b ≤ c
f : ((n : ℕ) → X n) → ℝ≥0∞
hf : Measurable f
⊢ lmarginalPartialTraj κ a b (lmarginalPartialTraj κ b c f) = lmarginalPartialTraj κ a c f

Tactic:
by

Goal state after:
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 : Kernel α γ
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
inst✝¹ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
a : α
h : κ a ≪ η a
⊢ (η.withDensity (κ.rnDeriv η)) a = κ a

Tactic:
by

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)
⊢ IsProjectiveLimit (infinitePi μ) fun I ↦ Measure.pi fun i ↦ μ ↑i

Tactic:
by

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)
⊢ IsProbabilityMeasure (infinitePi μ)

Tactic:
by

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

Goal state before:
pp: X : ℕ → Type u_1
mX : (n : ℕ) → MeasurableSpace (X n)
a b : ℕ
κ : (n : ℕ) → Kernel ((i : ↥(Iic n)) → X ↑i) (X (n + 1))
inst✝ : ∀ (n : ℕ), IsMarkovKernel (κ n)
c : ℕ
f : ((n : ℕ) → X n) → ℝ≥0∞
mf : Measurable f
hf : DependsOn f ↑(Iic a)
hab : a ≤ b
x : (n : ℕ) → X n
⊢ Measurable (restrict₂ ⋯)

Tactic:
by

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

Goal state before:
pp: α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
κ : Kernel α γ
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
inst✝¹ : IsFiniteKernel κ
f : α → γ → ℝ≥0∞
inst✝ : IsFiniteKernel (κ.withDensity f)
hf : Measurable (Function.uncurry f)
a : α
h_ae : (κ.withDensity f).rnDeriv κ a =ᵐ[κ a] ∂(κ.withDensity f) a/∂κ a
hf' : ∀ (a : α), Measurable (f a)
x : γ
hx1 : (κ.withDensity f).rnDeriv κ a x = (∂(κ.withDensity f) a/∂κ a) x
hx2 : (∂(κ a).withDensity (f a)/∂κ a) x = f a x
⊢ (κ.withDensity f).rnDeriv κ a x = f a x

Tactic:
hx1,

Goal state after:
α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
κ : Kernel α γ
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
inst✝¹ : IsFiniteKernel κ
f : α → γ → ℝ≥0∞
inst✝ : IsFiniteKernel (κ.withDensity f)
hf : Measurable (Function.uncurry f)
a : α
h_ae : (κ.withDensity f).rnDeriv κ a =ᵐ[κ a] ∂(κ.withDensity f) a/∂κ a
hf' : ∀ (a : α), Measurable (f a)
x : γ
hx1 : (κ.withDensity f).rnDeriv κ a x = (∂(κ.withDensity f) a/∂κ a) x
hx2 : (∂(κ a).withDensity (f a)/∂κ a) x = f a x
⊢ (∂(κ.withDensity f) a/∂κ a) x = f a x
Module: Mathlib.Probability.Kernel.RadonNikodym

Goal state before:
pp: α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
κ : Kernel α γ
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
inst✝¹ : IsFiniteKernel κ
f : α → γ → ℝ≥0∞
inst✝ : IsFiniteKernel (κ.withDensity f)
hf : Measurable (Function.uncurry f)
a : α
⊢ (κ.withDensity f).rnDeriv κ a =ᵐ[κ a] f a

Tactic:
by

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

Goal state before:
pp: X : ℕ → Type u_1
mX : (n : ℕ) → MeasurableSpace (X n)
a b : ℕ
κ : (n : ℕ) → Kernel ((i : ↥(Iic n)) → X ↑i) (X (n + 1))
inst✝ : ∀ (n : ℕ), IsMarkovKernel (κ n)
c : ℕ
f : ((n : ℕ) → X n) → ℝ≥0∞
mf : Measurable f
hf : DependsOn f ↑(Iic a)
hab : a ≤ b
⊢ lmarginalPartialTraj κ b c f = f

Tactic:
by

Goal state after:
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 : Kernel α γ
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
inst✝¹ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
a : α
h_ac : κ a ≪ η a
⊢ (∀ᵐ (b : γ) ∂η a, κ.rnDeriv η a b = 1) ↔ κ a = η a

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Kernel.Composition.AbsolutelyContinuous

Goal state before:
pp: α : Type u_1
β : Type u_2
mα : MeasurableSpace α
mβ : MeasurableSpace β
κ η : Kernel α β
inst✝² : IsFiniteKernel κ
inst✝¹ : IsFiniteKernel η
inst✝ : MeasurableSpace.CountableOrCountablyGenerated α β
μ ν : Measure α
hκη : ∀ᵐ (a : α) ∂μ, κ a ⟂ₘ η a
hμ : SFinite μ
hν : SFinite ν
s : Set (α × β) := κ.mutuallySingularSet η
hs : MeasurableSet s
h_eq : ∀ (a : α), Prod.mk a ⁻¹' s = κ.mutuallySingularSetSlice η a
a : α
⊢ (η a) (Prod.mk a ⁻¹' s) = 0

Tactic:
by

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

Goal state before:
pp: X : ℕ → Type u_1
mX : (n : ℕ) → MeasurableSpace (X n)
a b c : ℕ
κ : (n : ℕ) → Kernel ((i : ↥(Iic n)) → X ↑i) (X (n + 1))
inst✝ : ∀ (n : ℕ), IsMarkovKernel (κ n)
d : ℕ
f : ((n : ℕ) → X n) → ℝ≥0∞
mf : Measurable f
hf : DependsOn f ↑(Iic a)
hac : a ≤ c
had : a ≤ d
⊢ lmarginalPartialTraj κ b c f = lmarginalPartialTraj κ b d f

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Kernel.Composition.AbsolutelyContinuous

Goal state before:
pp: α : Type u_1
β : Type u_2
mα : MeasurableSpace α
mβ : MeasurableSpace β
κ η : Kernel α β
inst✝² : IsFiniteKernel κ
inst✝¹ : IsFiniteKernel η
inst✝ : MeasurableSpace.CountableOrCountablyGenerated α β
μ ν : Measure α
hκη : ∀ᵐ (a : α) ∂μ, κ a ⟂ₘ η a
hμ : SFinite μ
hν : SFinite ν
s : Set (α × β) := κ.mutuallySingularSet η
hs : MeasurableSet s
h_eq : ∀ (a : α), Prod.mk a ⁻¹' s = κ.mutuallySingularSetSlice η a
h1 : ∀ (a : α), (η a) (Prod.mk a ⁻¹' s) = 0
⊢ ∀ᵐ (a : α) ∂μ, (κ a) (Prod.mk a ⁻¹' s)ᶜ = 0

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Kernel.Composition.AbsolutelyContinuous

Goal state before:
pp: α : Type u_1
β : Type u_2
mα : MeasurableSpace α
mβ : MeasurableSpace β
κ η : Kernel α β
inst✝² : IsFiniteKernel κ
inst✝¹ : IsFiniteKernel η
inst✝ : MeasurableSpace.CountableOrCountablyGenerated α β
μ ν : Measure α
hκη : ∀ᵐ (a : α) ∂μ, κ a ⟂ₘ η a
⊢ μ ⊗ₘ κ ⟂ₘ ν ⊗ₘ η

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Kernel.Composition.AbsolutelyContinuous

Goal state before:
pp: α : Type u_1
β : Type u_2
mα : MeasurableSpace α
mβ : MeasurableSpace β
κ η : Kernel α β
inst✝² : IsFiniteKernel κ
inst✝¹ : IsFiniteKernel η
inst✝ : MeasurableSpace.CountableOrCountablyGenerated α β
μ ν : Measure α
hκη : ∀ᵐ (a : α) ∂ν, κ a ⟂ₘ η a
⊢ μ ⊗ₘ κ ⟂ₘ ν ⊗ₘ η

Tactic:
by

Goal state after:
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
hpos : ∀ (x : (i : ℕ) → X i) (n : ℕ), ε ≤ lmarginalPartialTraj κ p (a n) (χ n) (updateFinset x (Iic p) x₀)
χ_le : ∀ (n : ℕ) (x : (n : ℕ) → X n), χ n x ≤ 1
ind : (k : ℕ) → ((i : ↥(Iic k)) → X ↑i) → X (k + 1)
hind :
  ∀ (k : ℕ) (y : (i : ↥(Iic k)) → X ↑i),
    (∀ (x : (i : ℕ) → X i) (n : ℕ), ε ≤ lmarginalPartialTraj κ k (a n) (χ n) (updateFinset x (Iic k) y)) →
      ∀ (x : (i : ℕ) → X i) (n : ℕ),
        ε ≤ lmarginalPartialTraj κ (k + 1) (a n) (χ n) (update (updateFinset x (Iic k) y) (k + 1) (ind k y))
z : (n : ℕ) → X n := iterateInduction x₀ ind
main :
  ∀ (k : ℕ),
    p ≤ k →
      ∀ (x : (i : ℕ) → X i) (n : ℕ), ε ≤ lmarginalPartialTraj κ k (a n) (χ n) (updateFinset x (Iic k) (frestrictLe k z))
aux :
  ∀ (x : (i : ℕ) → X i) (n : ℕ),
    (trajContent κ x₀) (A n) = lmarginalPartialTraj κ p (a n) (χ n) (updateFinset x (Iic p) x₀)
this : 0 ≠ ε
n : ℕ
⊢ 0 < χ n z

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Kernel.Composition.AbsolutelyContinuous

Goal state before:
pp: α : Type u_1
β : Type u_2
mα : MeasurableSpace α
mβ : MeasurableSpace β
μ ν : Measure α
κ η : Kernel α β
inst✝³ : IsFiniteKernel κ
inst✝² : IsFiniteKernel η
inst✝¹ : MeasurableSpace.CountableOrCountablyGenerated α β
inst✝ : SFinite μ
h : μ ⊗ₘ κ ≪ ν ⊗ₘ η
this : ∀ᵐ (a : α) ∂μ, (κ.singularPart η) a = 0
⊢ ∀ᵐ (a : α) ∂μ, κ a ≪ η a

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Kernel.Composition.AbsolutelyContinuous

Goal state before:
pp: α : Type u_1
β : Type u_2
mα : MeasurableSpace α
mβ : MeasurableSpace β
μ ν : Measure α
κ η : Kernel α β
inst✝³ : IsFiniteKernel κ
inst✝² : IsFiniteKernel η
inst✝¹ : MeasurableSpace.CountableOrCountablyGenerated α β
inst✝ : SFinite μ
h : μ ⊗ₘ κ ≪ ν ⊗ₘ η
⊢ ∀ᵐ (a : α) ∂μ, κ a ≪ η a

Tactic:
by

Goal state after: