Module: Mathlib.MeasureTheory.Measure.Prokhorov

Goal state before:
pp: 𝓧 : Type u_1
m𝓧 : MeasurableSpace 𝓧
inst✝² : PseudoMetricSpace 𝓧
inst✝¹ : OpensMeasurableSpace 𝓧
inst✝ : SecondCountableTopology 𝓧
S : Set (ProbabilityMeasure 𝓧)
U : ℕ → Set 𝓧
O : ∀ (i : ℕ), IsOpen[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] (U i)
Cov : ⋃ i, U i = univ
hcomp : IsCompact (closure[ProbabilityMeasure.instTopologicalSpace] S)
ε : ℝ
hε' : 0 ≤ ε
hε : 0 < ε
hεbound : ε ≤ 1
μ : ℕ → ProbabilityMeasure 𝓧
hμInS : ∀ (k : ℕ), μ k ∈ S
hcontradiction : ∀ (k : ℕ), ↑((μ k) (⋃ i, ⋃ (_ : i ≤ k), U i)) ≤ 1 - ↑(NNReal.mk ε hε')
μlim : ProbabilityMeasure 𝓧
left✝ : μlim ∈ closure[ProbabilityMeasure.instTopologicalSpace] S
sub : ℕ → ℕ
hsubmono : StrictMono sub
hμconverges : Tendsto (μ ∘ sub) atTop (𝓝 μlim)
n : ℕ
hopen : IsOpen[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] (⋃ i, ⋃ (_ : i ≤ n), U i)
this : ↑(μlim (⋃ i, ⋃ (_ : i ≤ n), U i)) ≤ liminf (fun i ↦ ↑((μ (sub i)) (⋃ i, ⋃ (_ : i ≤ n), U i))) atTop
⊢ ↑(μlim (⋃ i, ⋃ (_ : i ≤ n), U i)) ≤ liminf (fun k ↦ ↑((μ (sub k)) (⋃ i, ⋃ (_ : i ≤ n), U i))) atTop

Tactic:
rw [← ofNNReal_liminf] at this

Goal state after:
𝓧 : Type u_1
m𝓧 : MeasurableSpace 𝓧
inst✝² : PseudoMetricSpace 𝓧
inst✝¹ : OpensMeasurableSpace 𝓧
inst✝ : SecondCountableTopology 𝓧
S : Set (ProbabilityMeasure 𝓧)
U : ℕ → Set 𝓧
O : ∀ (i : ℕ), IsOpen[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] (U i)
Cov : ⋃ i, U i = univ
hcomp : IsCompact (closure[ProbabilityMeasure.instTopologicalSpace] S)
ε : ℝ
hε' : 0 ≤ ε
hε : 0 < ε
hεbound : ε ≤ 1
μ : ℕ → ProbabilityMeasure 𝓧
hμInS : ∀ (k : ℕ), μ k ∈ S
hcontradiction : ∀ (k : ℕ), ↑((μ k) (⋃ i, ⋃ (_ : i ≤ k), U i)) ≤ 1 - ↑(NNReal.mk ε hε')
μlim : ProbabilityMeasure 𝓧
left✝ : μlim ∈ closure[ProbabilityMeasure.instTopologicalSpace] S
sub : ℕ → ℕ
hsubmono : StrictMono sub
hμconverges : Tendsto (μ ∘ sub) atTop (𝓝 μlim)
n : ℕ
hopen : IsOpen[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] (⋃ i, ⋃ (_ : i ≤ n), U i)
this : ↑(μlim (⋃ i, ⋃ (_ : i ≤ n), U i)) ≤ ↑(liminf (fun i ↦ (μ (sub i)) (⋃ i, ⋃ (_ : i ≤ n), U i)) atTop)
⊢ ↑(μlim (⋃ i, ⋃ (_ : i ≤ n), U i)) ≤ liminf (fun k ↦ ↑((μ (sub k)) (⋃ i, ⋃ (_ : i ≤ n), U i))) atTop

𝓧 : Type u_1
m𝓧 : MeasurableSpace 𝓧
inst✝² : PseudoMetricSpace 𝓧
inst✝¹ : OpensMeasurableSpace 𝓧
inst✝ : SecondCountableTopology 𝓧
S : Set (ProbabilityMeasure 𝓧)
U : ℕ → Set 𝓧
O : ∀ (i : ℕ), IsOpen[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] (U i)
Cov : ⋃ i, U i = univ
hcomp : IsCompact (closure[ProbabilityMeasure.instTopologicalSpace] S)
ε : ℝ
hε' : 0 ≤ ε
hε : 0 < ε
hεbound : ε ≤ 1
μ : ℕ → ProbabilityMeasure 𝓧
hμInS : ∀ (k : ℕ), μ k ∈ S
hcontradiction : ∀ (k : ℕ), ↑((μ k) (⋃ i, ⋃ (_ : i ≤ k), U i)) ≤ 1 - ↑(NNReal.mk ε hε')
μlim : ProbabilityMeasure 𝓧
left✝ : μlim ∈ closure[ProbabilityMeasure.instTopologicalSpace] S
sub : ℕ → ℕ
hsubmono : StrictMono sub
hμconverges : Tendsto (μ ∘ sub) atTop (𝓝 μlim)
n : ℕ
hopen : IsOpen[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] (⋃ i, ⋃ (_ : i ≤ n), U i)
this : ↑(μlim (⋃ i, ⋃ (_ : i ≤ n), U i)) ≤ liminf (fun i ↦ ↑((μ (sub i)) (⋃ i, ⋃ (_ : i ≤ n), U i))) atTop
⊢ IsCoboundedUnder (fun x1 x2 ↦ x1 ≥ x2) atTop fun i ↦ (μ (sub i)) (⋃ i, ⋃ (_ : i ≤ n), U i)