α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u v : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
⊢ IsConnected (f ⁻¹' connectedComponent t)
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u v : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
⊢ IsConnected (f ⁻¹' connectedComponent t)
have hf : Surjective f := Surjective.of_comp fun t : β => (connected_fibers t).1
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u v : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
⊢ IsPreconnected (f ⁻¹' connectedComponent t)
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u v : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
⊢ IsConnected (f ⁻¹' connectedComponent t)
refine ⟨Nonempty.preimage connectedComponent_nonempty hf, ?_⟩
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u v : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
⊢ IsPreconnected (f ⁻¹' connectedComponent t)
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u v : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
⊢ IsPreconnected (f ⁻¹' connectedComponent t)
have hT : IsClosed (f ⁻¹' connectedComponent t) :=
  (hcl (connectedComponent t)).1 isClosed_connectedComponent
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u v : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
⊢ ∀ (u v : Set α),
    IsClosed u →
      IsClosed v →
        f ⁻¹' connectedComponent t ⊆ u ∪ v →
          Disjoint u v → f ⁻¹' connectedComponent t ⊆ u ∨ f ⁻¹' connectedComponent t ⊆ v
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u v : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
⊢ IsPreconnected (f ⁻¹' connectedComponent t)
rw [isPreconnected_iff_subset_of_fully_disjoint_closed hT]
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
⊢ f ⁻¹' connectedComponent t ⊆ u ∨ f ⁻¹' connectedComponent t ⊆ v
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u v : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
⊢ ∀ (u v : Set α),
    IsClosed u →
      IsClosed v →
        f ⁻¹' connectedComponent t ⊆ u ∪ v →
          Disjoint u v → f ⁻¹' connectedComponent t ⊆ u ∨ f ⁻¹' connectedComponent t ⊆ v
intro u v hu hv huv uv_disj
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
⊢ f ⁻¹' connectedComponent t ⊆ u ∨ f ⁻¹' connectedComponent t ⊆ v
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
⊢ f ⁻¹' connectedComponent t ⊆ u ∨ f ⁻¹' connectedComponent t ⊆ v
let T₁ := { t' ∈ connectedComponent t | f ⁻¹' {t'} ⊆ u }
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
⊢ f ⁻¹' connectedComponent t ⊆ u ∨ f ⁻¹' connectedComponent t ⊆ v
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
⊢ f ⁻¹' connectedComponent t ⊆ u ∨ f ⁻¹' connectedComponent t ⊆ v
let T₂ := { t' ∈ connectedComponent t | f ⁻¹' {t'} ⊆ v }
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
T₂_v : f ⁻¹' T₂ = f ⁻¹' connectedComponent t ∩ v
hT₁ : IsClosed T₁
⊢ f ⁻¹' connectedComponent t ⊆ u ∨ f ⁻¹' connectedComponent t ⊆ v
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
T₂_v : f ⁻¹' T₂ = f ⁻¹' connectedComponent t ∩ v
⊢ f ⁻¹' connectedComponent t ⊆ u ∨ f ⁻¹' connectedComponent t ⊆ v
have hT₁ : IsClosed T₁ := (hcl T₁).2 (T₁_u.symm ▸ IsClosed.inter hT hu)
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
T₂_v : f ⁻¹' T₂ = f ⁻¹' connectedComponent t ∩ v
hT₁ : IsClosed T₁
hT₂ : IsClosed T₂
⊢ f ⁻¹' connectedComponent t ⊆ u ∨ f ⁻¹' connectedComponent t ⊆ v
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
T₂_v : f ⁻¹' T₂ = f ⁻¹' connectedComponent t ∩ v
hT₁ : IsClosed T₁
⊢ f ⁻¹' connectedComponent t ⊆ u ∨ f ⁻¹' connectedComponent t ⊆ v
have hT₂ : IsClosed T₂ := (hcl T₂).2 (T₂_v.symm ▸ IsClosed.inter hT hv)
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
T₂_v : f ⁻¹' T₂ = f ⁻¹' connectedComponent t ∩ v
hT₁ : IsClosed T₁
hT₂ : IsClosed T₂
T_decomp : connectedComponent t ⊆ T₁ ∪ T₂
T_disjoint : Disjoint T₁ T₂
⊢ f ⁻¹' connectedComponent t ⊆ u ∨ f ⁻¹' connectedComponent t ⊆ v
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
T₂_v : f ⁻¹' T₂ = f ⁻¹' connectedComponent t ∩ v
hT₁ : IsClosed T₁
hT₂ : IsClosed T₂
T_decomp : connectedComponent t ⊆ T₁ ∪ T₂
⊢ f ⁻¹' connectedComponent t ⊆ u ∨ f ⁻¹' connectedComponent t ⊆ v
have T_disjoint : Disjoint T₁ T₂ := by
  refine' Disjoint.of_preimage hf _
  rw [T₁_u, T₂_v, disjoint_iff_inter_eq_empty, ← inter_inter_distrib_left, uv_disj.inter_eq,
    inter_empty]
case inl
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
T₂_v : f ⁻¹' T₂ = f ⁻¹' connectedComponent t ∩ v
hT₁ : IsClosed T₁
hT₂ : IsClosed T₂
T_decomp : connectedComponent t ⊆ T₁ ∪ T₂
T_disjoint : Disjoint T₁ T₂
h : connectedComponent t ⊆ T₁
⊢ f ⁻¹' connectedComponent t ⊆ u ∨ f ⁻¹' connectedComponent t ⊆ v

case inr
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
T₂_v : f ⁻¹' T₂ = f ⁻¹' connectedComponent t ∩ v
hT₁ : IsClosed T₁
hT₂ : IsClosed T₂
T_decomp : connectedComponent t ⊆ T₁ ∪ T₂
T_disjoint : Disjoint T₁ T₂
h : connectedComponent t ⊆ T₂
⊢ f ⁻¹' connectedComponent t ⊆ u ∨ f ⁻¹' connectedComponent t ⊆ v
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
T₂_v : f ⁻¹' T₂ = f ⁻¹' connectedComponent t ∩ v
hT₁ : IsClosed T₁
hT₂ : IsClosed T₂
T_decomp : connectedComponent t ⊆ T₁ ∪ T₂
T_disjoint : Disjoint T₁ T₂
⊢ f ⁻¹' connectedComponent t ⊆ u ∨ f ⁻¹' connectedComponent t ⊆ v
cases' (isPreconnected_iff_subset_of_fully_disjoint_closed isClosed_connectedComponent).1
  isPreconnected_connectedComponent T₁ T₂ hT₁ hT₂ T_decomp T_disjoint with h h
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
t' : β
ht' : t' ∈ connectedComponent t
⊢ f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
⊢ ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
intro t' ht'
case a
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
t' : β
ht' : t' ∈ connectedComponent t
⊢ f ⁻¹' {t'} ⊆ u ∪ v

case a
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
t' : β
ht' : t' ∈ connectedComponent t
⊢ f ⁻¹' {t'} ∩ (u ∩ v) = ∅
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
t' : β
ht' : t' ∈ connectedComponent t
⊢ f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
apply isPreconnected_iff_subset_of_disjoint_closed.1 (connected_fibers t').2 u v hu hv
no goals
case a
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
t' : β
ht' : t' ∈ connectedComponent t
⊢ f ⁻¹' {t'} ∩ (u ∩ v) = ∅
rw [uv_disj.inter_eq, inter_empty]
no goals
case a
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
t' : β
ht' : t' ∈ connectedComponent t
⊢ f ⁻¹' {t'} ⊆ u ∪ v
exact Subset.trans (preimage_mono (singleton_subset_iff.2 ht')) huv
case a
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
⊢ f ⁻¹' T₁ ⊆ f ⁻¹' connectedComponent t ∩ u

case a
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
⊢ f ⁻¹' connectedComponent t ∩ u ⊆ f ⁻¹' T₁
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
⊢ f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
apply eq_of_subset_of_subset
case a.intro
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
a : α
hat : a ∈ f ⁻¹' connectedComponent t
hau : a ∈ u
⊢ a ∈ f ⁻¹' T₁
case a
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
⊢ f ⁻¹' connectedComponent t ∩ u ⊆ f ⁻¹' T₁
rintro a ⟨hat, hau⟩
case a.intro.left
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
a : α
hat : a ∈ f ⁻¹' connectedComponent t
hau : a ∈ u
⊢ f a ∈ connectedComponent t

case a.intro.right
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
a : α
hat : a ∈ f ⁻¹' connectedComponent t
hau : a ∈ u
⊢ f ⁻¹' {f a} ⊆ u
case a.intro
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
a : α
hat : a ∈ f ⁻¹' connectedComponent t
hau : a ∈ u
⊢ a ∈ f ⁻¹' T₁
constructor
case a.intro.right
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
a : α
hat : a ∈ f ⁻¹' connectedComponent t
hau : a ∈ u
h : f ⁻¹' {f a} ⊆ v
⊢ False
case a.intro.right
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
a : α
hat : a ∈ f ⁻¹' connectedComponent t
hau : a ∈ u
⊢ f ⁻¹' {f a} ⊆ u
refine (fiber_decomp (f a) (mem_preimage.1 hat)).resolve_right fun h => ?_
no goals
case a.intro.right
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
a : α
hat : a ∈ f ⁻¹' connectedComponent t
hau : a ∈ u
h : f ⁻¹' {f a} ⊆ v
⊢ False
exact uv_disj.subset_compl_right hau (h rfl)
case a
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
⊢ (⋃ (y : β) (_ : y ∈ T₁), f ⁻¹' {y}) ⊆ f ⁻¹' connectedComponent t ∩ u
case a
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
⊢ f ⁻¹' T₁ ⊆ f ⁻¹' connectedComponent t ∩ u
rw [← biUnion_preimage_singleton]
case a
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
t' : β
ht' : t' ∈ T₁
⊢ f ⁻¹' {t'} ⊆ f ⁻¹' connectedComponent t
case a
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
⊢ (⋃ (y : β) (_ : y ∈ T₁), f ⁻¹' {y}) ⊆ f ⁻¹' connectedComponent t ∩ u
refine' iUnion₂_subset fun t' ht' => subset_inter _ ht'.2
case a
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
t' : β
ht' : t' ∈ T₁
⊢ t' ∈ connectedComponent t
case a
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
t' : β
ht' : t' ∈ T₁
⊢ f ⁻¹' {t'} ⊆ f ⁻¹' connectedComponent t
rw [hf.preimage_subset_preimage_iff, singleton_subset_iff]
no goals
case a
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
t' : β
ht' : t' ∈ T₁
⊢ t' ∈ connectedComponent t
exact ht'.1
no goals
case a.intro.left
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
a : α
hat : a ∈ f ⁻¹' connectedComponent t
hau : a ∈ u
⊢ f a ∈ connectedComponent t
exact mem_preimage.1 hat
case a
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
⊢ f ⁻¹' T₂ ⊆ f ⁻¹' connectedComponent t ∩ v

case a
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
⊢ f ⁻¹' connectedComponent t ∩ v ⊆ f ⁻¹' T₂
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
⊢ f ⁻¹' T₂ = f ⁻¹' connectedComponent t ∩ v
apply eq_of_subset_of_subset
case a.intro
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
a : α
hat : a ∈ f ⁻¹' connectedComponent t
hav : a ∈ v
⊢ a ∈ f ⁻¹' T₂
case a
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
⊢ f ⁻¹' connectedComponent t ∩ v ⊆ f ⁻¹' T₂
rintro a ⟨hat, hav⟩
case a.intro.left
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
a : α
hat : a ∈ f ⁻¹' connectedComponent t
hav : a ∈ v
⊢ f a ∈ connectedComponent t

case a.intro.right
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
a : α
hat : a ∈ f ⁻¹' connectedComponent t
hav : a ∈ v
⊢ f ⁻¹' {f a} ⊆ v
case a.intro
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
a : α
hat : a ∈ f ⁻¹' connectedComponent t
hav : a ∈ v
⊢ a ∈ f ⁻¹' T₂
constructor
case a
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
⊢ (⋃ (y : β) (_ : y ∈ T₂), f ⁻¹' {y}) ⊆ f ⁻¹' connectedComponent t ∩ v
case a
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
⊢ f ⁻¹' T₂ ⊆ f ⁻¹' connectedComponent t ∩ v
rw [← biUnion_preimage_singleton]
case a
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
t' : β
ht' : t' ∈ T₂
⊢ f ⁻¹' {t'} ⊆ f ⁻¹' connectedComponent t
case a
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
⊢ (⋃ (y : β) (_ : y ∈ T₂), f ⁻¹' {y}) ⊆ f ⁻¹' connectedComponent t ∩ v
refine' iUnion₂_subset fun t' ht' => subset_inter _ ht'.2
case a
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
t' : β
ht' : t' ∈ T₂
⊢ t' ∈ connectedComponent t
case a
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
t' : β
ht' : t' ∈ T₂
⊢ f ⁻¹' {t'} ⊆ f ⁻¹' connectedComponent t
rw [hf.preimage_subset_preimage_iff, singleton_subset_iff]
no goals
case a
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
t' : β
ht' : t' ∈ T₂
⊢ t' ∈ connectedComponent t
exact ht'.1
no goals
case a.intro.left
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
a : α
hat : a ∈ f ⁻¹' connectedComponent t
hav : a ∈ v
⊢ f a ∈ connectedComponent t
exact mem_preimage.1 hat
case a.intro.right
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
a : α
hat : a ∈ f ⁻¹' connectedComponent t
hav : a ∈ v
h : f ⁻¹' {f a} ⊆ u
⊢ False
case a.intro.right
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
a : α
hat : a ∈ f ⁻¹' connectedComponent t
hav : a ∈ v
⊢ f ⁻¹' {f a} ⊆ v
refine (fiber_decomp (f a) (mem_preimage.1 hat)).resolve_left fun h => ?_
no goals
case a.intro.right
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
a : α
hat : a ∈ f ⁻¹' connectedComponent t
hav : a ∈ v
h : f ⁻¹' {f a} ⊆ u
⊢ False
exact uv_disj.subset_compl_left hav (h rfl)
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
T₂_v : f ⁻¹' T₂ = f ⁻¹' connectedComponent t ∩ v
hT₁ : IsClosed T₁
hT₂ : IsClosed T₂
t' : β
ht' : t' ∈ connectedComponent t
⊢ t' ∈ T₁ ∨ t' ∈ T₂
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
T₂_v : f ⁻¹' T₂ = f ⁻¹' connectedComponent t ∩ v
hT₁ : IsClosed T₁
hT₂ : IsClosed T₂
t' : β
ht' : t' ∈ connectedComponent t
⊢ t' ∈ T₁ ∪ T₂
rw [mem_union t' T₁ T₂]
case inl
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
T₂_v : f ⁻¹' T₂ = f ⁻¹' connectedComponent t ∩ v
hT₁ : IsClosed T₁
hT₂ : IsClosed T₂
t' : β
ht' : t' ∈ connectedComponent t
htu : f ⁻¹' {t'} ⊆ u
⊢ t' ∈ T₁ ∨ t' ∈ T₂

case inr
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
T₂_v : f ⁻¹' T₂ = f ⁻¹' connectedComponent t ∩ v
hT₁ : IsClosed T₁
hT₂ : IsClosed T₂
t' : β
ht' : t' ∈ connectedComponent t
htv : f ⁻¹' {t'} ⊆ v
⊢ t' ∈ T₁ ∨ t' ∈ T₂
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
T₂_v : f ⁻¹' T₂ = f ⁻¹' connectedComponent t ∩ v
hT₁ : IsClosed T₁
hT₂ : IsClosed T₂
t' : β
ht' : t' ∈ connectedComponent t
⊢ t' ∈ T₁ ∨ t' ∈ T₂
cases' fiber_decomp t' ht' with htu htv
case inr.h
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
T₂_v : f ⁻¹' T₂ = f ⁻¹' connectedComponent t ∩ v
hT₁ : IsClosed T₁
hT₂ : IsClosed T₂
t' : β
ht' : t' ∈ connectedComponent t
htv : f ⁻¹' {t'} ⊆ v
⊢ t' ∈ T₂
case inr
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
T₂_v : f ⁻¹' T₂ = f ⁻¹' connectedComponent t ∩ v
hT₁ : IsClosed T₁
hT₂ : IsClosed T₂
t' : β
ht' : t' ∈ connectedComponent t
htv : f ⁻¹' {t'} ⊆ v
⊢ t' ∈ T₁ ∨ t' ∈ T₂
right
no goals
case inr.h
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
T₂_v : f ⁻¹' T₂ = f ⁻¹' connectedComponent t ∩ v
hT₁ : IsClosed T₁
hT₂ : IsClosed T₂
t' : β
ht' : t' ∈ connectedComponent t
htv : f ⁻¹' {t'} ⊆ v
⊢ t' ∈ T₂
exact ⟨ht', htv⟩
case inl.h
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
T₂_v : f ⁻¹' T₂ = f ⁻¹' connectedComponent t ∩ v
hT₁ : IsClosed T₁
hT₂ : IsClosed T₂
t' : β
ht' : t' ∈ connectedComponent t
htu : f ⁻¹' {t'} ⊆ u
⊢ t' ∈ T₁
case inl
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
T₂_v : f ⁻¹' T₂ = f ⁻¹' connectedComponent t ∩ v
hT₁ : IsClosed T₁
hT₂ : IsClosed T₂
t' : β
ht' : t' ∈ connectedComponent t
htu : f ⁻¹' {t'} ⊆ u
⊢ t' ∈ T₁ ∨ t' ∈ T₂
left
no goals
case inl.h
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
T₂_v : f ⁻¹' T₂ = f ⁻¹' connectedComponent t ∩ v
hT₁ : IsClosed T₁
hT₂ : IsClosed T₂
t' : β
ht' : t' ∈ connectedComponent t
htu : f ⁻¹' {t'} ⊆ u
⊢ t' ∈ T₁
exact ⟨ht', htu⟩
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
T₂_v : f ⁻¹' T₂ = f ⁻¹' connectedComponent t ∩ v
hT₁ : IsClosed T₁
hT₂ : IsClosed T₂
T_decomp : connectedComponent t ⊆ T₁ ∪ T₂
⊢ Disjoint (f ⁻¹' T₁) (f ⁻¹' T₂)
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
T₂_v : f ⁻¹' T₂ = f ⁻¹' connectedComponent t ∩ v
hT₁ : IsClosed T₁
hT₂ : IsClosed T₂
T_decomp : connectedComponent t ⊆ T₁ ∪ T₂
⊢ Disjoint T₁ T₂
refine' Disjoint.of_preimage hf _
no goals
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
T₂_v : f ⁻¹' T₂ = f ⁻¹' connectedComponent t ∩ v
hT₁ : IsClosed T₁
hT₂ : IsClosed T₂
T_decomp : connectedComponent t ⊆ T₁ ∪ T₂
⊢ Disjoint (f ⁻¹' T₁) (f ⁻¹' T₂)
rw [T₁_u, T₂_v, disjoint_iff_inter_eq_empty, ← inter_inter_distrib_left, uv_disj.inter_eq,
  inter_empty]
case inl.h
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
T₂_v : f ⁻¹' T₂ = f ⁻¹' connectedComponent t ∩ v
hT₁ : IsClosed T₁
hT₂ : IsClosed T₂
T_decomp : connectedComponent t ⊆ T₁ ∪ T₂
T_disjoint : Disjoint T₁ T₂
h : connectedComponent t ⊆ T₁
⊢ f ⁻¹' connectedComponent t ⊆ u
case inl
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
T₂_v : f ⁻¹' T₂ = f ⁻¹' connectedComponent t ∩ v
hT₁ : IsClosed T₁
hT₂ : IsClosed T₂
T_decomp : connectedComponent t ⊆ T₁ ∪ T₂
T_disjoint : Disjoint T₁ T₂
h : connectedComponent t ⊆ T₁
⊢ f ⁻¹' connectedComponent t ⊆ u ∨ f ⁻¹' connectedComponent t ⊆ v
left
case inl.h
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ ⊆ f ⁻¹' connectedComponent t ∩ u ∧ f ⁻¹' connectedComponent t ∩ u ⊆ f ⁻¹' T₁
T₂_v : f ⁻¹' T₂ = f ⁻¹' connectedComponent t ∩ v
hT₁ : IsClosed T₁
hT₂ : IsClosed T₂
T_decomp : connectedComponent t ⊆ T₁ ∪ T₂
T_disjoint : Disjoint T₁ T₂
h : connectedComponent t ⊆ T₁
⊢ f ⁻¹' connectedComponent t ⊆ u
case inl.h
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
T₂_v : f ⁻¹' T₂ = f ⁻¹' connectedComponent t ∩ v
hT₁ : IsClosed T₁
hT₂ : IsClosed T₂
T_decomp : connectedComponent t ⊆ T₁ ∪ T₂
T_disjoint : Disjoint T₁ T₂
h : connectedComponent t ⊆ T₁
⊢ f ⁻¹' connectedComponent t ⊆ u
rw [Subset.antisymm_iff] at T₁_u
case inl.h
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ ⊆ f ⁻¹' connectedComponent t ∩ u ∧ f ⁻¹' connectedComponent t ∩ u ⊆ f ⁻¹' T₁
T₂_v : f ⁻¹' T₂ = f ⁻¹' connectedComponent t ∩ v
hT₁ : IsClosed T₁
hT₂ : IsClosed T₂
T_decomp : connectedComponent t ⊆ T₁ ∪ T₂
T_disjoint : Disjoint T₁ T₂
h : connectedComponent t ⊆ T₁
⊢ f ⁻¹' connectedComponent t ⊆ f ⁻¹' T₁
case inl.h
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ ⊆ f ⁻¹' connectedComponent t ∩ u ∧ f ⁻¹' connectedComponent t ∩ u ⊆ f ⁻¹' T₁
T₂_v : f ⁻¹' T₂ = f ⁻¹' connectedComponent t ∩ v
hT₁ : IsClosed T₁
hT₂ : IsClosed T₂
T_decomp : connectedComponent t ⊆ T₁ ∪ T₂
T_disjoint : Disjoint T₁ T₂
h : connectedComponent t ⊆ T₁
⊢ f ⁻¹' connectedComponent t ⊆ u
suffices f ⁻¹' connectedComponent t ⊆ f ⁻¹' T₁
  from (this.trans T₁_u.1).trans (inter_subset_right _ _)
no goals
case inl.h
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ ⊆ f ⁻¹' connectedComponent t ∩ u ∧ f ⁻¹' connectedComponent t ∩ u ⊆ f ⁻¹' T₁
T₂_v : f ⁻¹' T₂ = f ⁻¹' connectedComponent t ∩ v
hT₁ : IsClosed T₁
hT₂ : IsClosed T₂
T_decomp : connectedComponent t ⊆ T₁ ∪ T₂
T_disjoint : Disjoint T₁ T₂
h : connectedComponent t ⊆ T₁
⊢ f ⁻¹' connectedComponent t ⊆ f ⁻¹' T₁
exact preimage_mono h
case inr.h
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
T₂_v : f ⁻¹' T₂ = f ⁻¹' connectedComponent t ∩ v
hT₁ : IsClosed T₁
hT₂ : IsClosed T₂
T_decomp : connectedComponent t ⊆ T₁ ∪ T₂
T_disjoint : Disjoint T₁ T₂
h : connectedComponent t ⊆ T₂
⊢ f ⁻¹' connectedComponent t ⊆ v
case inr
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
T₂_v : f ⁻¹' T₂ = f ⁻¹' connectedComponent t ∩ v
hT₁ : IsClosed T₁
hT₂ : IsClosed T₂
T_decomp : connectedComponent t ⊆ T₁ ∪ T₂
T_disjoint : Disjoint T₁ T₂
h : connectedComponent t ⊆ T₂
⊢ f ⁻¹' connectedComponent t ⊆ u ∨ f ⁻¹' connectedComponent t ⊆ v
right
case inr.h
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
T₂_v : f ⁻¹' T₂ ⊆ f ⁻¹' connectedComponent t ∩ v ∧ f ⁻¹' connectedComponent t ∩ v ⊆ f ⁻¹' T₂
hT₁ : IsClosed T₁
hT₂ : IsClosed T₂
T_decomp : connectedComponent t ⊆ T₁ ∪ T₂
T_disjoint : Disjoint T₁ T₂
h : connectedComponent t ⊆ T₂
⊢ f ⁻¹' connectedComponent t ⊆ v
case inr.h
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
T₂_v : f ⁻¹' T₂ = f ⁻¹' connectedComponent t ∩ v
hT₁ : IsClosed T₁
hT₂ : IsClosed T₂
T_decomp : connectedComponent t ⊆ T₁ ∪ T₂
T_disjoint : Disjoint T₁ T₂
h : connectedComponent t ⊆ T₂
⊢ f ⁻¹' connectedComponent t ⊆ v
rw [Subset.antisymm_iff] at T₂_v
case inr.h
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
T₂_v : f ⁻¹' T₂ ⊆ f ⁻¹' connectedComponent t ∩ v ∧ f ⁻¹' connectedComponent t ∩ v ⊆ f ⁻¹' T₂
hT₁ : IsClosed T₁
hT₂ : IsClosed T₂
T_decomp : connectedComponent t ⊆ T₁ ∪ T₂
T_disjoint : Disjoint T₁ T₂
h : connectedComponent t ⊆ T₂
⊢ f ⁻¹' connectedComponent t ⊆ f ⁻¹' T₂
case inr.h
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
T₂_v : f ⁻¹' T₂ ⊆ f ⁻¹' connectedComponent t ∩ v ∧ f ⁻¹' connectedComponent t ∩ v ⊆ f ⁻¹' T₂
hT₁ : IsClosed T₁
hT₂ : IsClosed T₂
T_decomp : connectedComponent t ⊆ T₁ ∪ T₂
T_disjoint : Disjoint T₁ T₂
h : connectedComponent t ⊆ T₂
⊢ f ⁻¹' connectedComponent t ⊆ v
suffices f ⁻¹' connectedComponent t ⊆ f ⁻¹' T₂
  from (this.trans T₂_v.1).trans (inter_subset_right _ _)
no goals
case inr.h
α : Type u
β : Type v
ι : Type ?u.107968
π : ι → Type ?u.107973
inst✝¹ : TopologicalSpace α
s t✝ u✝ v✝ : Set α
inst✝ : TopologicalSpace β
f : α → β
connected_fibers : ∀ (t : β), IsConnected (f ⁻¹' {t})
hcl : ∀ (T : Set β), IsClosed T ↔ IsClosed (f ⁻¹' T)
t : β
hf : Surjective f
hT : IsClosed (f ⁻¹' connectedComponent t)
u v : Set α
hu : IsClosed u
hv : IsClosed v
huv : f ⁻¹' connectedComponent t ⊆ u ∪ v
uv_disj : Disjoint u v
T₁ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ u}
T₂ : Set β := {t' | t' ∈ connectedComponent t ∧ f ⁻¹' {t'} ⊆ v}
fiber_decomp : ∀ (t' : β), t' ∈ connectedComponent t → f ⁻¹' {t'} ⊆ u ∨ f ⁻¹' {t'} ⊆ v
T₁_u : f ⁻¹' T₁ = f ⁻¹' connectedComponent t ∩ u
T₂_v : f ⁻¹' T₂ ⊆ f ⁻¹' connectedComponent t ∩ v ∧ f ⁻¹' connectedComponent t ∩ v ⊆ f ⁻¹' T₂
hT₁ : IsClosed T₁
hT₂ : IsClosed T₂
T_decomp : connectedComponent t ⊆ T₁ ∪ T₂
T_disjoint : Disjoint T₁ T₂
h : connectedComponent t ⊆ T₂
⊢ f ⁻¹' connectedComponent t ⊆ f ⁻¹' T₂
exact preimage_mono h