Theorem: essSup_map_measure_of_measurable
File: Mathlib/MeasureTheory/Function/EssSup.lean

Proof steps:
state_before: α : Type u_1
β : Type u_2
m : MeasurableSpace α
μ ν : Measure α
inst✝⁵ : CompleteLattice β
γ : Type u_3
mγ : MeasurableSpace γ
f : α → γ
g : γ → β
inst✝⁴ : MeasurableSpace β
inst✝³ : TopologicalSpace β
inst✝² : SecondCountableTopology β
inst✝¹ : OrderClosedTopology β
inst✝ : OpensMeasurableSpace β
hg : Measurable g
hf : AEMeasurable f μ
⊢ essSup g (Measure.map f μ) = essSup (g ∘ f) μ
state_after: α : Type u_1
β : Type u_2
m : MeasurableSpace α
μ ν : Measure α
inst✝⁵ : CompleteLattice β
γ : Type u_3
mγ : MeasurableSpace γ
f : α → γ
g : γ → β
inst✝⁴ : MeasurableSpace β
inst✝³ : TopologicalSpace β
inst✝² : SecondCountableTopology β
inst✝¹ : OrderClosedTopology β
inst✝ : OpensMeasurableSpace β
hg : Measurable g
hf : AEMeasurable f μ
⊢ essSup g (Measure.map f μ) ≤ essSup (g ∘ f) μ
tactic: refine le_antisymm ?_ (essSup_comp_le_essSup_map_measure hf)
state_before: α : Type u_1
β : Type u_2
m : MeasurableSpace α
μ ν : Measure α
inst✝⁵ : CompleteLattice β
γ : Type u_3
mγ : MeasurableSpace γ
f : α → γ
g : γ → β
inst✝⁴ : MeasurableSpace β
inst✝³ : TopologicalSpace β
inst✝² : SecondCountableTopology β
inst✝¹ : OrderClosedTopology β
inst✝ : OpensMeasurableSpace β
hg : Measurable g
hf : AEMeasurable f μ
⊢ essSup g (Measure.map f μ) ≤ essSup (g ∘ f) μ
state_after: α : Type u_1
β : Type u_2
m : MeasurableSpace α
μ ν : Measure α
inst✝⁵ : CompleteLattice β
γ : Type u_3
mγ : MeasurableSpace γ
f : α → γ
g : γ → β
inst✝⁴ : MeasurableSpace β
inst✝³ : TopologicalSpace β
inst✝² : SecondCountableTopology β
inst✝¹ : OrderClosedTopology β
inst✝ : OpensMeasurableSpace β
hg : Measurable g
hf : AEMeasurable f μ
c : β
h_le : ∀ᶠ (n : β) in map (g ∘ f) (ae μ), n ≤ c
⊢ ∀ᶠ (n : β) in map g (ae (Measure.map f μ)), n ≤ c
tactic: refine limsSup_le_limsSup (by isBoundedDefault) (by isBoundedDefault) (fun c h_le => ?_)
state_before: α : Type u_1
β : Type u_2
m : MeasurableSpace α
μ ν : Measure α
inst✝⁵ : CompleteLattice β
γ : Type u_3
mγ : MeasurableSpace γ
f : α → γ
g : γ → β
inst✝⁴ : MeasurableSpace β
inst✝³ : TopologicalSpace β
inst✝² : SecondCountableTopology β
inst✝¹ : OrderClosedTopology β
inst✝ : OpensMeasurableSpace β
hg : Measurable g
hf : AEMeasurable f μ
c : β
h_le : ∀ᶠ (n : β) in map (g ∘ f) (ae μ), n ≤ c
⊢ ∀ᶠ (n : β) in map g (ae (Measure.map f μ)), n ≤ c
state_after: α : Type u_1
β : Type u_2
m : MeasurableSpace α
μ ν : Measure α
inst✝⁵ : CompleteLattice β
γ : Type u_3
mγ : MeasurableSpace γ
f : α → γ
g : γ → β
inst✝⁴ : MeasurableSpace β
inst✝³ : TopologicalSpace β
inst✝² : SecondCountableTopology β
inst✝¹ : OrderClosedTopology β
inst✝ : OpensMeasurableSpace β
hg : Measurable g
hf : AEMeasurable f μ
c : β
h_le : ∀ᵐ (a : α) ∂μ, (g ∘ f) a ≤ c
⊢ ∀ᵐ (a : γ) ∂Measure.map f μ, g a ≤ c
tactic: rw [eventually_map] at h_le ⊢
state_before: α : Type u_1
β : Type u_2
m : MeasurableSpace α
μ ν : Measure α
inst✝⁵ : CompleteLattice β
γ : Type u_3
mγ : MeasurableSpace γ
f : α → γ
g : γ → β
inst✝⁴ : MeasurableSpace β
inst✝³ : TopologicalSpace β
inst✝² : SecondCountableTopology β
inst✝¹ : OrderClosedTopology β
inst✝ : OpensMeasurableSpace β
hg : Measurable g
hf : AEMeasurable f μ
c : β
h_le : ∀ᵐ (a : α) ∂μ, (g ∘ f) a ≤ c
⊢ ∀ᵐ (a : γ) ∂Measure.map f μ, g a ≤ c
state_after: α : Type u_1
β : Type u_2
m : MeasurableSpace α
μ ν : Measure α
inst✝⁵ : CompleteLattice β
γ : Type u_3
mγ : MeasurableSpace γ
f : α → γ
g : γ → β
inst✝⁴ : MeasurableSpace β
inst✝³ : TopologicalSpace β
inst✝² : SecondCountableTopology β
inst✝¹ : OrderClosedTopology β
inst✝ : OpensMeasurableSpace β
hg : Measurable g
hf : AEMeasurable f μ
c : β
h_le : ∀ᵐ (a : α) ∂μ, (g ∘ f) a ≤ c
⊢ ∀ᵐ (x : α) ∂μ, g (f x) ≤ c
tactic: rw [ae_map_iff hf (measurableSet_le hg measurable_const)]
state_before: α : Type u_1
β : Type u_2
m : MeasurableSpace α
μ ν : Measure α
inst✝⁵ : CompleteLattice β
γ : Type u_3
mγ : MeasurableSpace γ
f : α → γ
g : γ → β
inst✝⁴ : MeasurableSpace β
inst✝³ : TopologicalSpace β
inst✝² : SecondCountableTopology β
inst✝¹ : OrderClosedTopology β
inst✝ : OpensMeasurableSpace β
hg : Measurable g
hf : AEMeasurable f μ
c : β
h_le : ∀ᵐ (a : α) ∂μ, (g ∘ f) a ≤ c
⊢ ∀ᵐ (x : α) ∂μ, g (f x) ≤ c
state_after: no goals
tactic: exact h_le