Theorem: isProperMap_iff_isClosedMap_ultrafilter
File: Mathlib/Topology/ProperMap.lean

tactic: constructor <;> intro H
state_before: X✝ : Type u_1
Y✝ : Type u_2
Z : Type u_3
W : Type u_4
ι : Type u_5
inst✝⁵ : TopologicalSpace X✝
inst✝⁴ : TopologicalSpace Y✝
inst✝³ : TopologicalSpace Z
inst✝² : TopologicalSpace W
f✝ : X✝ → Y✝
g : Y✝ → Z
X : Type u
Y : Type v
inst✝¹ : TopologicalSpace X
inst✝ : TopologicalSpace Y
f : X → Y
⊢ IsProperMap f ↔ Continuous f ∧ IsClosedMap (Prod.map f id)
state_after: case mp
X✝ : Type u_1
Y✝ : Type u_2
Z : Type u_3
W : Type u_4
ι : Type u_5
inst✝⁵ : TopologicalSpace X✝
inst✝⁴ : TopologicalSpace Y✝
inst✝³ : TopologicalSpace Z
inst✝² : TopologicalSpace W
f✝ : X✝ → Y✝
g : Y✝ → Z
X : Type u
Y : Type v
inst✝¹ : TopologicalSpace X
inst✝ : TopologicalSpace Y
f : X → Y
H : IsProperMap f
⊢ Continuous f ∧ IsClosedMap (Prod.map f id)

case mpr
X✝ : Type u_1
Y✝ : Type u_2
Z : Type u_3
W : Type u_4
ι : Type u_5
inst✝⁵ : TopologicalSpace X✝
inst✝⁴ : TopologicalSpace Y✝
inst✝³ : TopologicalSpace Z
inst✝² : TopologicalSpace W
f✝ : X✝ → Y✝
g : Y✝ → Z
X : Type u
Y : Type v
inst✝¹ : TopologicalSpace X
inst✝ : TopologicalSpace Y
f : X → Y
H : Continuous f ∧ IsClosedMap (Prod.map f id)
⊢ IsProperMap f

tactic: exact ⟨H.continuous, H.universally_closed _⟩
state_before: case mp
X✝ : Type u_1
Y✝ : Type u_2
Z : Type u_3
W : Type u_4
ι : Type u_5
inst✝⁵ : TopologicalSpace X✝
inst✝⁴ : TopologicalSpace Y✝
inst✝³ : TopologicalSpace Z
inst✝² : TopologicalSpace W
f✝ : X✝ → Y✝
g : Y✝ → Z
X : Type u
Y : Type v
inst✝¹ : TopologicalSpace X
inst✝ : TopologicalSpace Y
f : X → Y
H : IsProperMap f
⊢ Continuous f ∧ IsClosedMap (Prod.map f id)
state_after: no goals

tactic: rw [isProperMap_iff_ultrafilter]
state_before: case mpr
X✝ : Type u_1
Y✝ : Type u_2
Z : Type u_3
W : Type u_4
ι : Type u_5
inst✝⁵ : TopologicalSpace X✝
inst✝⁴ : TopologicalSpace Y✝
inst✝³ : TopologicalSpace Z
inst✝² : TopologicalSpace W
f✝ : X✝ → Y✝
g : Y✝ → Z
X : Type u
Y : Type v
inst✝¹ : TopologicalSpace X
inst✝ : TopologicalSpace Y
f : X → Y
H : Continuous f ∧ IsClosedMap (Prod.map f id)
⊢ IsProperMap f
state_after: case mpr
X✝ : Type u_1
Y✝ : Type u_2
Z : Type u_3
W : Type u_4
ι : Type u_5
inst✝⁵ : TopologicalSpace X✝
inst✝⁴ : TopologicalSpace Y✝
inst✝³ : TopologicalSpace Z
inst✝² : TopologicalSpace W
f✝ : X✝ → Y✝
g : Y✝ → Z
X : Type u
Y : Type v
inst✝¹ : TopologicalSpace X
inst✝ : TopologicalSpace Y
f : X → Y
H : Continuous f ∧ IsClosedMap (Prod.map f id)
⊢ Continuous f ∧ ∀ ⦃𝒰 : Ultrafilter X⦄ ⦃y : Y⦄, Tendsto f (↑𝒰) (𝓝 y) → ∃ x, f x = y ∧ ↑𝒰 ≤ 𝓝 x

tactic: refine ⟨H.1, fun 𝒰 y hy ↦ ?_⟩
state_before: case mpr
X✝ : Type u_1
Y✝ : Type u_2
Z : Type u_3
W : Type u_4
ι : Type u_5
inst✝⁵ : TopologicalSpace X✝
inst✝⁴ : TopologicalSpace Y✝
inst✝³ : TopologicalSpace Z
inst✝² : TopologicalSpace W
f✝ : X✝ → Y✝
g : Y✝ → Z
X : Type u
Y : Type v
inst✝¹ : TopologicalSpace X
inst✝ : TopologicalSpace Y
f : X → Y
H : Continuous f ∧ IsClosedMap (Prod.map f id)
⊢ Continuous f ∧ ∀ ⦃𝒰 : Ultrafilter X⦄ ⦃y : Y⦄, Tendsto f (↑𝒰) (𝓝 y) → ∃ x, f x = y ∧ ↑𝒰 ≤ 𝓝 x
state_after: case mpr
X✝ : Type u_1
Y✝ : Type u_2
Z : Type u_3
W : Type u_4
ι : Type u_5
inst✝⁵ : TopologicalSpace X✝
inst✝⁴ : TopologicalSpace Y✝
inst✝³ : TopologicalSpace Z
inst✝² : TopologicalSpace W
f✝ : X✝ → Y✝
g : Y✝ → Z
X : Type u
Y : Type v
inst✝¹ : TopologicalSpace X
inst✝ : TopologicalSpace Y
f : X → Y
H : Continuous f ∧ IsClosedMap (Prod.map f id)
𝒰 : Ultrafilter X
y : Y
hy : Tendsto f (↑𝒰) (𝓝 y)
⊢ ∃ x, f x = y ∧ ↑𝒰 ≤ 𝓝 x

tactic: let F : Set (X × Ultrafilter X) := closure {xℱ | xℱ.2 = pure xℱ.1}
state_before: case mpr
X✝ : Type u_1
Y✝ : Type u_2
Z : Type u_3
W : Type u_4
ι : Type u_5
inst✝⁵ : TopologicalSpace X✝
inst✝⁴ : TopologicalSpace Y✝
inst✝³ : TopologicalSpace Z
inst✝² : TopologicalSpace W
f✝ : X✝ → Y✝
g : Y✝ → Z
X : Type u
Y : Type v
inst✝¹ : TopologicalSpace X
inst✝ : TopologicalSpace Y
f : X → Y
H : Continuous f ∧ IsClosedMap (Prod.map f id)
𝒰 : Ultrafilter X
y : Y
hy : Tendsto f (↑𝒰) (𝓝 y)
⊢ ∃ x, f x = y ∧ ↑𝒰 ≤ 𝓝 x
state_after: case mpr
X✝ : Type u_1
Y✝ : Type u_2
Z : Type u_3
W : Type u_4
ι : Type u_5
inst✝⁵ : TopologicalSpace X✝
inst✝⁴ : TopologicalSpace Y✝
inst✝³ : TopologicalSpace Z
inst✝² : TopologicalSpace W
f✝ : X✝ → Y✝
g : Y✝ → Z
X : Type u
Y : Type v
inst✝¹ : TopologicalSpace X
inst✝ : TopologicalSpace Y
f : X → Y
H : Continuous f ∧ IsClosedMap (Prod.map f id)
𝒰 : Ultrafilter X
y : Y
hy : Tendsto f (↑𝒰) (𝓝 y)
F : Set (X × Ultrafilter X) := closure {xℱ | xℱ.2 = pure xℱ.1}
⊢ ∃ x, f x = y ∧ ↑𝒰 ≤ 𝓝 x

tactic: have := H.2 F isClosed_closure
state_before: case mpr
X✝ : Type u_1
Y✝ : Type u_2
Z : Type u_3
W : Type u_4
ι : Type u_5
inst✝⁵ : TopologicalSpace X✝
inst✝⁴ : TopologicalSpace Y✝
inst✝³ : TopologicalSpace Z
inst✝² : TopologicalSpace W
f✝ : X✝ → Y✝
g : Y✝ → Z
X : Type u
Y : Type v
inst✝¹ : TopologicalSpace X
inst✝ : TopologicalSpace Y
f : X → Y
H : Continuous f ∧ IsClosedMap (Prod.map f id)
𝒰 : Ultrafilter X
y : Y
hy : Tendsto f (↑𝒰) (𝓝 y)
F : Set (X × Ultrafilter X) := closure {xℱ | xℱ.2 = pure xℱ.1}
⊢ ∃ x, f x = y ∧ ↑𝒰 ≤ 𝓝 x
state_after: case mpr
X✝ : Type u_1
Y✝ : Type u_2
Z : Type u_3
W : Type u_4
ι : Type u_5
inst✝⁵ : TopologicalSpace X✝
inst✝⁴ : TopologicalSpace Y✝
inst✝³ : TopologicalSpace Z
inst✝² : TopologicalSpace W
f✝ : X✝ → Y✝
g : Y✝ → Z
X : Type u
Y : Type v
inst✝¹ : TopologicalSpace X
inst✝ : TopologicalSpace Y
f : X → Y
H : Continuous f ∧ IsClosedMap (Prod.map f id)
𝒰 : Ultrafilter X
y : Y
hy : Tendsto f (↑𝒰) (𝓝 y)
F : Set (X × Ultrafilter X) := closure {xℱ | xℱ.2 = pure xℱ.1}
this : IsClosed (Prod.map f id '' F)
⊢ ∃ x, f x = y ∧ ↑𝒰 ≤ 𝓝 x

tactic: have : (y, 𝒰) ∈ Prod.map f id '' F :=
  this.mem_of_tendsto (hy.prod_mk_nhds (Ultrafilter.tendsto_pure_self 𝒰))
    (eventually_of_forall fun x ↦ ⟨⟨x, pure x⟩, subset_closure rfl, rfl⟩)
state_before: case mpr
X✝ : Type u_1
Y✝ : Type u_2
Z : Type u_3
W : Type u_4
ι : Type u_5
inst✝⁵ : TopologicalSpace X✝
inst✝⁴ : TopologicalSpace Y✝
inst✝³ : TopologicalSpace Z
inst✝² : TopologicalSpace W
f✝ : X✝ → Y✝
g : Y✝ → Z
X : Type u
Y : Type v
inst✝¹ : TopologicalSpace X
inst✝ : TopologicalSpace Y
f : X → Y
H : Continuous f ∧ IsClosedMap (Prod.map f id)
𝒰 : Ultrafilter X
y : Y
hy : Tendsto f (↑𝒰) (𝓝 y)
F : Set (X × Ultrafilter X) := closure {xℱ | xℱ.2 = pure xℱ.1}
this : IsClosed (Prod.map f id '' F)
⊢ ∃ x, f x = y ∧ ↑𝒰 ≤ 𝓝 x
state_after: case mpr
X✝ : Type u_1
Y✝ : Type u_2
Z : Type u_3
W : Type u_4
ι : Type u_5
inst✝⁵ : TopologicalSpace X✝
inst✝⁴ : TopologicalSpace Y✝
inst✝³ : TopologicalSpace Z
inst✝² : TopologicalSpace W
f✝ : X✝ → Y✝
g : Y✝ → Z
X : Type u
Y : Type v
inst✝¹ : TopologicalSpace X
inst✝ : TopologicalSpace Y
f : X → Y
H : Continuous f ∧ IsClosedMap (Prod.map f id)
𝒰 : Ultrafilter X
y : Y
hy : Tendsto f (↑𝒰) (𝓝 y)
F : Set (X × Ultrafilter X) := closure {xℱ | xℱ.2 = pure xℱ.1}
this✝ : IsClosed (Prod.map f id '' F)
this : (y, 𝒰) ∈ Prod.map f id '' F
⊢ ∃ x, f x = y ∧ ↑𝒰 ≤ 𝓝 x

tactic: rcases this with ⟨⟨x, _⟩, hx, ⟨_, _⟩⟩
state_before: case mpr
X✝ : Type u_1
Y✝ : Type u_2
Z : Type u_3
W : Type u_4
ι : Type u_5
inst✝⁵ : TopologicalSpace X✝
inst✝⁴ : TopologicalSpace Y✝
inst✝³ : TopologicalSpace Z
inst✝² : TopologicalSpace W
f✝ : X✝ → Y✝
g : Y✝ → Z
X : Type u
Y : Type v
inst✝¹ : TopologicalSpace X
inst✝ : TopologicalSpace Y
f : X → Y
H : Continuous f ∧ IsClosedMap (Prod.map f id)
𝒰 : Ultrafilter X
y : Y
hy : Tendsto f (↑𝒰) (𝓝 y)
F : Set (X × Ultrafilter X) := closure {xℱ | xℱ.2 = pure xℱ.1}
this✝ : IsClosed (Prod.map f id '' F)
this : (y, 𝒰) ∈ Prod.map f id '' F
⊢ ∃ x, f x = y ∧ ↑𝒰 ≤ 𝓝 x
state_after: case mpr.intro.mk.intro.refl
X✝ : Type u_1
Y✝ : Type u_2
Z : Type u_3
W : Type u_4
ι : Type u_5
inst✝⁵ : TopologicalSpace X✝
inst✝⁴ : TopologicalSpace Y✝
inst✝³ : TopologicalSpace Z
inst✝² : TopologicalSpace W
f✝ : X✝ → Y✝
g : Y✝ → Z
X : Type u
Y : Type v
inst✝¹ : TopologicalSpace X
inst✝ : TopologicalSpace Y
f : X → Y
H : Continuous f ∧ IsClosedMap (Prod.map f id)
F : Set (X × Ultrafilter X) := closure {xℱ | xℱ.2 = pure xℱ.1}
this : IsClosed (Prod.map f id '' F)
x : X
snd✝ : Ultrafilter X
hx : (x, snd✝) ∈ F
hy : Tendsto f (↑(id snd✝)) (𝓝 (f x))
⊢ ∃ x_1, f x_1 = f x ∧ ↑(id snd✝) ≤ 𝓝 x_1

tactic: refine ⟨x, rfl, fun U hU ↦ Ultrafilter.compl_not_mem_iff.mp fun hUc ↦ ?_⟩
state_before: case mpr.intro.mk.intro.refl
X✝ : Type u_1
Y✝ : Type u_2
Z : Type u_3
W : Type u_4
ι : Type u_5
inst✝⁵ : TopologicalSpace X✝
inst✝⁴ : TopologicalSpace Y✝
inst✝³ : TopologicalSpace Z
inst✝² : TopologicalSpace W
f✝ : X✝ → Y✝
g : Y✝ → Z
X : Type u
Y : Type v
inst✝¹ : TopologicalSpace X
inst✝ : TopologicalSpace Y
f : X → Y
H : Continuous f ∧ IsClosedMap (Prod.map f id)
F : Set (X × Ultrafilter X) := closure {xℱ | xℱ.2 = pure xℱ.1}
this : IsClosed (Prod.map f id '' F)
x : X
snd✝ : Ultrafilter X
hx : (x, snd✝) ∈ F
hy : Tendsto f (↑(id snd✝)) (𝓝 (f x))
⊢ ∃ x_1, f x_1 = f x ∧ ↑(id snd✝) ≤ 𝓝 x_1
state_after: case mpr.intro.mk.intro.refl
X✝ : Type u_1
Y✝ : Type u_2
Z : Type u_3
W : Type u_4
ι : Type u_5
inst✝⁵ : TopologicalSpace X✝
inst✝⁴ : TopologicalSpace Y✝
inst✝³ : TopologicalSpace Z
inst✝² : TopologicalSpace W
f✝ : X✝ → Y✝
g : Y✝ → Z
X : Type u
Y : Type v
inst✝¹ : TopologicalSpace X
inst✝ : TopologicalSpace Y
f : X → Y
H : Continuous f ∧ IsClosedMap (Prod.map f id)
F : Set (X × Ultrafilter X) := closure {xℱ | xℱ.2 = pure xℱ.1}
this : IsClosed (Prod.map f id '' F)
x : X
snd✝ : Ultrafilter X
hx : (x, snd✝) ∈ F
hy : Tendsto f (↑(id snd✝)) (𝓝 (f x))
U : Set X
hU : U ∈ 𝓝 x
hUc : Uᶜ ∈ id snd✝
⊢ False

tactic: rw [mem_closure_iff_nhds] at hx
state_before: case mpr.intro.mk.intro.refl
X✝ : Type u_1
Y✝ : Type u_2
Z : Type u_3
W : Type u_4
ι : Type u_5
inst✝⁵ : TopologicalSpace X✝
inst✝⁴ : TopologicalSpace Y✝
inst✝³ : TopologicalSpace Z
inst✝² : TopologicalSpace W
f✝ : X✝ → Y✝
g : Y✝ → Z
X : Type u
Y : Type v
inst✝¹ : TopologicalSpace X
inst✝ : TopologicalSpace Y
f : X → Y
H : Continuous f ∧ IsClosedMap (Prod.map f id)
F : Set (X × Ultrafilter X) := closure {xℱ | xℱ.2 = pure xℱ.1}
this : IsClosed (Prod.map f id '' F)
x : X
snd✝ : Ultrafilter X
hx : (x, snd✝) ∈ F
hy : Tendsto f (↑(id snd✝)) (𝓝 (f x))
U : Set X
hU : U ∈ 𝓝 x
hUc : Uᶜ ∈ id snd✝
⊢ False
state_after: case mpr.intro.mk.intro.refl
X✝ : Type u_1
Y✝ : Type u_2
Z : Type u_3
W : Type u_4
ι : Type u_5
inst✝⁵ : TopologicalSpace X✝
inst✝⁴ : TopologicalSpace Y✝
inst✝³ : TopologicalSpace Z
inst✝² : TopologicalSpace W
f✝ : X✝ → Y✝
g : Y✝ → Z
X : Type u
Y : Type v
inst✝¹ : TopologicalSpace X
inst✝ : TopologicalSpace Y
f : X → Y
H : Continuous f ∧ IsClosedMap (Prod.map f id)
F : Set (X × Ultrafilter X) := closure {xℱ | xℱ.2 = pure xℱ.1}
this : IsClosed (Prod.map f id '' F)
x : X
snd✝ : Ultrafilter X
hx : ∀ t ∈ 𝓝 (x, snd✝), (t ∩ {xℱ | xℱ.2 = pure xℱ.1}).Nonempty
hy : Tendsto f (↑(id snd✝)) (𝓝 (f x))
U : Set X
hU : U ∈ 𝓝 x
hUc : Uᶜ ∈ id snd✝
⊢ False

tactic: rcases hx (U ×ˢ {𝒢 | Uᶜ ∈ 𝒢}) (prod_mem_nhds hU ((ultrafilter_isOpen_basic _).mem_nhds hUc))
  with ⟨⟨y, 𝒢⟩, ⟨⟨hy : y ∈ U, hy' : Uᶜ ∈ 𝒢⟩, rfl : 𝒢 = pure y⟩⟩
state_before: case mpr.intro.mk.intro.refl
X✝ : Type u_1
Y✝ : Type u_2
Z : Type u_3
W : Type u_4
ι : Type u_5
inst✝⁵ : TopologicalSpace X✝
inst✝⁴ : TopologicalSpace Y✝
inst✝³ : TopologicalSpace Z
inst✝² : TopologicalSpace W
f✝ : X✝ → Y✝
g : Y✝ → Z
X : Type u
Y : Type v
inst✝¹ : TopologicalSpace X
inst✝ : TopologicalSpace Y
f : X → Y
H : Continuous f ∧ IsClosedMap (Prod.map f id)
F : Set (X × Ultrafilter X) := closure {xℱ | xℱ.2 = pure xℱ.1}
this : IsClosed (Prod.map f id '' F)
x : X
snd✝ : Ultrafilter X
hx : ∀ t ∈ 𝓝 (x, snd✝), (t ∩ {xℱ | xℱ.2 = pure xℱ.1}).Nonempty
hy : Tendsto f (↑(id snd✝)) (𝓝 (f x))
U : Set X
hU : U ∈ 𝓝 x
hUc : Uᶜ ∈ id snd✝
⊢ False
state_after: case mpr.intro.mk.intro.refl.intro.mk.intro.intro
X✝ : Type u_1
Y✝ : Type u_2
Z : Type u_3
W : Type u_4
ι : Type u_5
inst✝⁵ : TopologicalSpace X✝
inst✝⁴ : TopologicalSpace Y✝
inst✝³ : TopologicalSpace Z
inst✝² : TopologicalSpace W
f✝ : X✝ → Y✝
g : Y✝ → Z
X : Type u
Y : Type v
inst✝¹ : TopologicalSpace X
inst✝ : TopologicalSpace Y
f : X → Y
H : Continuous f ∧ IsClosedMap (Prod.map f id)
F : Set (X × Ultrafilter X) := closure {xℱ | xℱ.2 = pure xℱ.1}
this : IsClosed (Prod.map f id '' F)
x : X
snd✝ : Ultrafilter X
hx : ∀ t ∈ 𝓝 (x, snd✝), (t ∩ {xℱ | xℱ.2 = pure xℱ.1}).Nonempty
hy✝ : Tendsto f (↑(id snd✝)) (𝓝 (f x))
U : Set X
hU : U ∈ 𝓝 x
hUc : Uᶜ ∈ id snd✝
y : X
hy : y ∈ U
hy' : Uᶜ ∈ pure y
⊢ False

tactic: exact hy' hy
state_before: case mpr.intro.mk.intro.refl.intro.mk.intro.intro
X✝ : Type u_1
Y✝ : Type u_2
Z : Type u_3
W : Type u_4
ι : Type u_5
inst✝⁵ : TopologicalSpace X✝
inst✝⁴ : TopologicalSpace Y✝
inst✝³ : TopologicalSpace Z
inst✝² : TopologicalSpace W
f✝ : X✝ → Y✝
g : Y✝ → Z
X : Type u
Y : Type v
inst✝¹ : TopologicalSpace X
inst✝ : TopologicalSpace Y
f : X → Y
H : Continuous f ∧ IsClosedMap (Prod.map f id)
F : Set (X × Ultrafilter X) := closure {xℱ | xℱ.2 = pure xℱ.1}
this : IsClosed (Prod.map f id '' F)
x : X
snd✝ : Ultrafilter X
hx : ∀ t ∈ 𝓝 (x, snd✝), (t ∩ {xℱ | xℱ.2 = pure xℱ.1}).Nonempty
hy✝ : Tendsto f (↑(id snd✝)) (𝓝 (f x))
U : Set X
hU : U ∈ 𝓝 x
hUc : Uᶜ ∈ id snd✝
y : X
hy : y ∈ U
hy' : Uᶜ ∈ pure y
⊢ False
state_after: no goals