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simps.symm_apply (h : α ≃ₜ β) : β → α
h.symm initialize_simps_projections homeomorph (to_equiv_to_fun → apply, to_equiv_inv_fun → symm_apply, -to_equiv)
def
homeomorph.simps.symm_apply
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "homeomorph" ]
See Note [custom simps projection]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coe_to_equiv (h : α ≃ₜ β) : ⇑h.to_equiv = h
rfl
lemma
homeomorph.coe_to_equiv
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coe_symm_to_equiv (h : α ≃ₜ β) : ⇑h.to_equiv.symm = h.symm
rfl
lemma
homeomorph.coe_symm_to_equiv
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
to_equiv_injective : function.injective (to_equiv : α ≃ₜ β → α ≃ β)
| ⟨e, h₁, h₂⟩ ⟨e', h₁', h₂'⟩ rfl := rfl
lemma
homeomorph.to_equiv_injective
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
ext {h h' : α ≃ₜ β} (H : ∀ x, h x = h' x) : h = h'
to_equiv_injective $ equiv.ext H
lemma
homeomorph.ext
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "equiv.ext" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
symm_symm (h : α ≃ₜ β) : h.symm.symm = h
ext $ λ _, rfl
lemma
homeomorph.symm_symm
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
refl (α : Type*) [topological_space α] : α ≃ₜ α
{ continuous_to_fun := continuous_id, continuous_inv_fun := continuous_id, to_equiv := equiv.refl α }
def
homeomorph.refl
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "continuous_id", "equiv.refl", "topological_space" ]
Identity map as a homeomorphism.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
trans (h₁ : α ≃ₜ β) (h₂ : β ≃ₜ γ) : α ≃ₜ γ
{ continuous_to_fun := h₂.continuous_to_fun.comp h₁.continuous_to_fun, continuous_inv_fun := h₁.continuous_inv_fun.comp h₂.continuous_inv_fun, to_equiv := equiv.trans h₁.to_equiv h₂.to_equiv }
def
homeomorph.trans
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "equiv.trans" ]
Composition of two homeomorphisms.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
trans_apply (h₁ : α ≃ₜ β) (h₂ : β ≃ₜ γ) (a : α) : h₁.trans h₂ a = h₂ (h₁ a)
rfl
lemma
homeomorph.trans_apply
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
homeomorph_mk_coe_symm (a : equiv α β) (b c) : ((homeomorph.mk a b c).symm : β → α) = a.symm
rfl
lemma
homeomorph.homeomorph_mk_coe_symm
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "equiv" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
refl_symm : (homeomorph.refl α).symm = homeomorph.refl α
rfl
lemma
homeomorph.refl_symm
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "homeomorph.refl" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
continuous (h : α ≃ₜ β) : continuous h
h.continuous_to_fun
lemma
homeomorph.continuous
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "continuous" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
continuous_symm (h : α ≃ₜ β) : continuous (h.symm)
h.continuous_inv_fun
lemma
homeomorph.continuous_symm
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "continuous" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
apply_symm_apply (h : α ≃ₜ β) (x : β) : h (h.symm x) = x
h.to_equiv.apply_symm_apply x
lemma
homeomorph.apply_symm_apply
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
symm_apply_apply (h : α ≃ₜ β) (x : α) : h.symm (h x) = x
h.to_equiv.symm_apply_apply x
lemma
homeomorph.symm_apply_apply
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
self_trans_symm (h : α ≃ₜ β) : h.trans h.symm = homeomorph.refl α
by { ext, apply symm_apply_apply }
lemma
homeomorph.self_trans_symm
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "homeomorph.refl" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
symm_trans_self (h : α ≃ₜ β) : h.symm.trans h = homeomorph.refl β
by { ext, apply apply_symm_apply }
lemma
homeomorph.symm_trans_self
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "homeomorph.refl" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
bijective (h : α ≃ₜ β) : function.bijective h
h.to_equiv.bijective
lemma
homeomorph.bijective
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
injective (h : α ≃ₜ β) : function.injective h
h.to_equiv.injective
lemma
homeomorph.injective
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
surjective (h : α ≃ₜ β) : function.surjective h
h.to_equiv.surjective
lemma
homeomorph.surjective
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
change_inv (f : α ≃ₜ β) (g : β → α) (hg : function.right_inverse g f) : α ≃ₜ β
have g = f.symm, from funext (λ x, calc g x = f.symm (f (g x)) : (f.left_inv (g x)).symm ... = f.symm x : by rw hg x), { to_fun := f, inv_fun := g, left_inv := by convert f.left_inv, right_inv := by convert f.right_inv, continuous_to_fun := f.continuous, continuous_inv_...
def
homeomorph.change_inv
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "inv_fun" ]
Change the homeomorphism `f` to make the inverse function definitionally equal to `g`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
symm_comp_self (h : α ≃ₜ β) : ⇑h.symm ∘ ⇑h = id
funext h.symm_apply_apply
lemma
homeomorph.symm_comp_self
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
self_comp_symm (h : α ≃ₜ β) : ⇑h ∘ ⇑h.symm = id
funext h.apply_symm_apply
lemma
homeomorph.self_comp_symm
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
range_coe (h : α ≃ₜ β) : range h = univ
h.surjective.range_eq
lemma
homeomorph.range_coe
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
image_symm (h : α ≃ₜ β) : image h.symm = preimage h
funext h.symm.to_equiv.image_eq_preimage
lemma
homeomorph.image_symm
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
preimage_symm (h : α ≃ₜ β) : preimage h.symm = image h
(funext h.to_equiv.image_eq_preimage).symm
lemma
homeomorph.preimage_symm
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
image_preimage (h : α ≃ₜ β) (s : set β) : h '' (h ⁻¹' s) = s
h.to_equiv.image_preimage s
lemma
homeomorph.image_preimage
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
preimage_image (h : α ≃ₜ β) (s : set α) : h ⁻¹' (h '' s) = s
h.to_equiv.preimage_image s
lemma
homeomorph.preimage_image
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
inducing (h : α ≃ₜ β) : inducing h
inducing_of_inducing_compose h.continuous h.symm.continuous $ by simp only [symm_comp_self, inducing_id]
lemma
homeomorph.inducing
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "inducing", "inducing_id", "inducing_of_inducing_compose" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
induced_eq (h : α ≃ₜ β) : topological_space.induced h ‹_› = ‹_›
h.inducing.1.symm
lemma
homeomorph.induced_eq
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "topological_space.induced" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
quotient_map (h : α ≃ₜ β) : quotient_map h
quotient_map.of_quotient_map_compose h.symm.continuous h.continuous $ by simp only [self_comp_symm, quotient_map.id]
lemma
homeomorph.quotient_map
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "quotient_map", "quotient_map.id", "quotient_map.of_quotient_map_compose" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coinduced_eq (h : α ≃ₜ β) : topological_space.coinduced h ‹_› = ‹_›
h.quotient_map.2.symm
lemma
homeomorph.coinduced_eq
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "topological_space.coinduced" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
embedding (h : α ≃ₜ β) : embedding h
⟨h.inducing, h.injective⟩
lemma
homeomorph.embedding
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "embedding" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
of_embedding (f : α → β) (hf : embedding f) : α ≃ₜ (set.range f)
{ continuous_to_fun := hf.continuous.subtype_mk _, continuous_inv_fun := by simp [hf.continuous_iff, continuous_subtype_coe], to_equiv := equiv.of_injective f hf.inj }
def
homeomorph.of_embedding
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "continuous_subtype_coe", "embedding", "equiv.of_injective", "set.range" ]
Homeomorphism given an embedding.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
second_countable_topology [topological_space.second_countable_topology β] (h : α ≃ₜ β) : topological_space.second_countable_topology α
h.inducing.second_countable_topology
lemma
homeomorph.second_countable_topology
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "topological_space.second_countable_topology" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_compact_image {s : set α} (h : α ≃ₜ β) : is_compact (h '' s) ↔ is_compact s
h.embedding.is_compact_iff_is_compact_image.symm
lemma
homeomorph.is_compact_image
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "is_compact" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_compact_preimage {s : set β} (h : α ≃ₜ β) : is_compact (h ⁻¹' s) ↔ is_compact s
by rw ← image_symm; exact h.symm.is_compact_image
lemma
homeomorph.is_compact_preimage
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "is_compact" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
comap_cocompact (h : α ≃ₜ β) : comap h (cocompact β) = cocompact α
(comap_cocompact_le h.continuous).antisymm $ (has_basis_cocompact.le_basis_iff (has_basis_cocompact.comap h)).2 $ λ K hK, ⟨h ⁻¹' K, h.is_compact_preimage.2 hK, subset.rfl⟩
lemma
homeomorph.comap_cocompact
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
map_cocompact (h : α ≃ₜ β) : map h (cocompact α) = cocompact β
by rw [← h.comap_cocompact, map_comap_of_surjective h.surjective]
lemma
homeomorph.map_cocompact
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
compact_space [compact_space α] (h : α ≃ₜ β) : compact_space β
{ is_compact_univ := by { rw [← image_univ_of_surjective h.surjective, h.is_compact_image], apply compact_space.is_compact_univ } }
lemma
homeomorph.compact_space
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "compact_space", "is_compact_univ" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
t0_space [t0_space α] (h : α ≃ₜ β) : t0_space β
h.symm.embedding.t0_space
lemma
homeomorph.t0_space
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "t0_space" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
t1_space [t1_space α] (h : α ≃ₜ β) : t1_space β
h.symm.embedding.t1_space
lemma
homeomorph.t1_space
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "t1_space" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
t2_space [t2_space α] (h : α ≃ₜ β) : t2_space β
h.symm.embedding.t2_space
lemma
homeomorph.t2_space
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "t2_space" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
t3_space [t3_space α] (h : α ≃ₜ β) : t3_space β
h.symm.embedding.t3_space
lemma
homeomorph.t3_space
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "t3_space" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
dense_embedding (h : α ≃ₜ β) : dense_embedding h
{ dense := h.surjective.dense_range, .. h.embedding }
lemma
homeomorph.dense_embedding
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "dense", "dense_embedding" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_open_preimage (h : α ≃ₜ β) {s : set β} : is_open (h ⁻¹' s) ↔ is_open s
h.quotient_map.is_open_preimage
lemma
homeomorph.is_open_preimage
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "is_open" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_open_image (h : α ≃ₜ β) {s : set α} : is_open (h '' s) ↔ is_open s
by rw [← preimage_symm, is_open_preimage]
lemma
homeomorph.is_open_image
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "is_open" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_open_map (h : α ≃ₜ β) : is_open_map h
λ s, h.is_open_image.2
lemma
homeomorph.is_open_map
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "is_open_map" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_closed_preimage (h : α ≃ₜ β) {s : set β} : is_closed (h ⁻¹' s) ↔ is_closed s
by simp only [← is_open_compl_iff, ← preimage_compl, is_open_preimage]
lemma
homeomorph.is_closed_preimage
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "is_closed", "is_open_compl_iff" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_closed_image (h : α ≃ₜ β) {s : set α} : is_closed (h '' s) ↔ is_closed s
by rw [← preimage_symm, is_closed_preimage]
lemma
homeomorph.is_closed_image
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "is_closed" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_closed_map (h : α ≃ₜ β) : is_closed_map h
λ s, h.is_closed_image.2
lemma
homeomorph.is_closed_map
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "is_closed_map" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
open_embedding (h : α ≃ₜ β) : open_embedding h
open_embedding_of_embedding_open h.embedding h.is_open_map
lemma
homeomorph.open_embedding
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "open_embedding", "open_embedding_of_embedding_open" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
closed_embedding (h : α ≃ₜ β) : closed_embedding h
closed_embedding_of_embedding_closed h.embedding h.is_closed_map
lemma
homeomorph.closed_embedding
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "closed_embedding", "closed_embedding_of_embedding_closed" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
normal_space [normal_space α] (h : α ≃ₜ β) : normal_space β
h.symm.closed_embedding.normal_space
lemma
homeomorph.normal_space
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "normal_space" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
preimage_closure (h : α ≃ₜ β) (s : set β) : h ⁻¹' (closure s) = closure (h ⁻¹' s)
h.is_open_map.preimage_closure_eq_closure_preimage h.continuous _
lemma
homeomorph.preimage_closure
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "closure" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
image_closure (h : α ≃ₜ β) (s : set α) : h '' (closure s) = closure (h '' s)
by rw [← preimage_symm, preimage_closure]
lemma
homeomorph.image_closure
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "closure" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
preimage_interior (h : α ≃ₜ β) (s : set β) : h⁻¹' (interior s) = interior (h ⁻¹' s)
h.is_open_map.preimage_interior_eq_interior_preimage h.continuous _
lemma
homeomorph.preimage_interior
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "interior" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
image_interior (h : α ≃ₜ β) (s : set α) : h '' (interior s) = interior (h '' s)
by rw [← preimage_symm, preimage_interior]
lemma
homeomorph.image_interior
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "interior" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
preimage_frontier (h : α ≃ₜ β) (s : set β) : h ⁻¹' (frontier s) = frontier (h ⁻¹' s)
h.is_open_map.preimage_frontier_eq_frontier_preimage h.continuous _
lemma
homeomorph.preimage_frontier
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "frontier" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
image_frontier (h : α ≃ₜ β) (s : set α) : h '' frontier s = frontier (h '' s)
by rw [←preimage_symm, preimage_frontier]
lemma
homeomorph.image_frontier
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "frontier" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
_root_.has_compact_mul_support.comp_homeomorph {M} [has_one M] {f : β → M} (hf : has_compact_mul_support f) (φ : α ≃ₜ β) : has_compact_mul_support (f ∘ φ)
hf.comp_closed_embedding φ.closed_embedding
lemma
has_compact_mul_support.comp_homeomorph
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "has_compact_mul_support" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
map_nhds_eq (h : α ≃ₜ β) (x : α) : map h (𝓝 x) = 𝓝 (h x)
h.embedding.map_nhds_of_mem _ (by simp)
lemma
homeomorph.map_nhds_eq
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
symm_map_nhds_eq (h : α ≃ₜ β) (x : α) : map h.symm (𝓝 (h x)) = 𝓝 x
by rw [h.symm.map_nhds_eq, h.symm_apply_apply]
lemma
homeomorph.symm_map_nhds_eq
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
nhds_eq_comap (h : α ≃ₜ β) (x : α) : 𝓝 x = comap h (𝓝 (h x))
h.embedding.to_inducing.nhds_eq_comap x
lemma
homeomorph.nhds_eq_comap
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
comap_nhds_eq (h : α ≃ₜ β) (y : β) : comap h (𝓝 y) = 𝓝 (h.symm y)
by rw [h.nhds_eq_comap, h.apply_symm_apply]
lemma
homeomorph.comap_nhds_eq
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
homeomorph_of_continuous_open (e : α ≃ β) (h₁ : continuous e) (h₂ : is_open_map e) : α ≃ₜ β
{ continuous_to_fun := h₁, continuous_inv_fun := begin rw continuous_def, intros s hs, convert ← h₂ s hs using 1, apply e.image_eq_preimage end, to_equiv := e }
def
homeomorph.homeomorph_of_continuous_open
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "continuous", "continuous_def", "is_open_map" ]
If an bijective map `e : α ≃ β` is continuous and open, then it is a homeomorphism.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
comp_continuous_on_iff (h : α ≃ₜ β) (f : γ → α) (s : set γ) : continuous_on (h ∘ f) s ↔ continuous_on f s
h.inducing.continuous_on_iff.symm
lemma
homeomorph.comp_continuous_on_iff
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "continuous_on" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
comp_continuous_iff (h : α ≃ₜ β) {f : γ → α} : continuous (h ∘ f) ↔ continuous f
h.inducing.continuous_iff.symm
lemma
homeomorph.comp_continuous_iff
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "continuous" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
comp_continuous_iff' (h : α ≃ₜ β) {f : β → γ} : continuous (f ∘ h) ↔ continuous f
h.quotient_map.continuous_iff.symm
lemma
homeomorph.comp_continuous_iff'
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "continuous" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
comp_continuous_at_iff (h : α ≃ₜ β) (f : γ → α) (x : γ) : continuous_at (h ∘ f) x ↔ continuous_at f x
h.inducing.continuous_at_iff.symm
lemma
homeomorph.comp_continuous_at_iff
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "continuous_at" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
comp_continuous_at_iff' (h : α ≃ₜ β) (f : β → γ) (x : α) : continuous_at (f ∘ h) x ↔ continuous_at f (h x)
h.inducing.continuous_at_iff' (by simp)
lemma
homeomorph.comp_continuous_at_iff'
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "continuous_at" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
comp_continuous_within_at_iff (h : α ≃ₜ β) (f : γ → α) (s : set γ) (x : γ) : continuous_within_at f s x ↔ continuous_within_at (h ∘ f) s x
h.inducing.continuous_within_at_iff
lemma
homeomorph.comp_continuous_within_at_iff
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "continuous_within_at" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
comp_is_open_map_iff (h : α ≃ₜ β) {f : γ → α} : is_open_map (h ∘ f) ↔ is_open_map f
begin refine ⟨_, λ hf, h.is_open_map.comp hf⟩, intros hf, rw [← function.comp.left_id f, ← h.symm_comp_self, function.comp.assoc], exact h.symm.is_open_map.comp hf, end
lemma
homeomorph.comp_is_open_map_iff
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "is_open_map" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
comp_is_open_map_iff' (h : α ≃ₜ β) {f : β → γ} : is_open_map (f ∘ h) ↔ is_open_map f
begin refine ⟨_, λ hf, hf.comp h.is_open_map⟩, intros hf, rw [← function.comp.right_id f, ← h.self_comp_symm, ← function.comp.assoc], exact hf.comp h.symm.is_open_map, end
lemma
homeomorph.comp_is_open_map_iff'
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "is_open_map" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
set_congr {s t : set α} (h : s = t) : s ≃ₜ t
{ continuous_to_fun := continuous_inclusion h.subset, continuous_inv_fun := continuous_inclusion h.symm.subset, to_equiv := equiv.set_congr h }
def
homeomorph.set_congr
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "continuous_inclusion", "equiv.set_congr" ]
If two sets are equal, then they are homeomorphic.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
sum_congr (h₁ : α ≃ₜ β) (h₂ : γ ≃ₜ δ) : α ⊕ γ ≃ₜ β ⊕ δ
{ continuous_to_fun := h₁.continuous.sum_map h₂.continuous, continuous_inv_fun := h₁.symm.continuous.sum_map h₂.symm.continuous, to_equiv := h₁.to_equiv.sum_congr h₂.to_equiv }
def
homeomorph.sum_congr
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[]
Sum of two homeomorphisms.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
prod_congr (h₁ : α ≃ₜ β) (h₂ : γ ≃ₜ δ) : α × γ ≃ₜ β × δ
{ continuous_to_fun := (h₁.continuous.comp continuous_fst).prod_mk (h₂.continuous.comp continuous_snd), continuous_inv_fun := (h₁.symm.continuous.comp continuous_fst).prod_mk (h₂.symm.continuous.comp continuous_snd), to_equiv := h₁.to_equiv.prod_congr h₂.to_equiv }
def
homeomorph.prod_congr
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "continuous_fst", "continuous_snd" ]
Product of two homeomorphisms.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
prod_congr_symm (h₁ : α ≃ₜ β) (h₂ : γ ≃ₜ δ) : (h₁.prod_congr h₂).symm = h₁.symm.prod_congr h₂.symm
rfl
lemma
homeomorph.prod_congr_symm
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coe_prod_congr (h₁ : α ≃ₜ β) (h₂ : γ ≃ₜ δ) : ⇑(h₁.prod_congr h₂) = prod.map h₁ h₂
rfl
lemma
homeomorph.coe_prod_congr
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
prod_comm : α × β ≃ₜ β × α
{ continuous_to_fun := continuous_snd.prod_mk continuous_fst, continuous_inv_fun := continuous_snd.prod_mk continuous_fst, to_equiv := equiv.prod_comm α β }
def
homeomorph.prod_comm
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "continuous_fst", "equiv.prod_comm" ]
`α × β` is homeomorphic to `β × α`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
prod_comm_symm : (prod_comm α β).symm = prod_comm β α
rfl
lemma
homeomorph.prod_comm_symm
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coe_prod_comm : ⇑(prod_comm α β) = prod.swap
rfl
lemma
homeomorph.coe_prod_comm
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "prod.swap" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
prod_assoc : (α × β) × γ ≃ₜ α × (β × γ)
{ continuous_to_fun := (continuous_fst.comp continuous_fst).prod_mk ((continuous_snd.comp continuous_fst).prod_mk continuous_snd), continuous_inv_fun := (continuous_fst.prod_mk (continuous_fst.comp continuous_snd)).prod_mk (continuous_snd.comp continuous_snd), to_equiv := equiv.prod_assoc α β γ }
def
homeomorph.prod_assoc
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "continuous_fst", "continuous_snd", "equiv.prod_assoc" ]
`(α × β) × γ` is homeomorphic to `α × (β × γ)`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
prod_punit : α × punit ≃ₜ α
{ to_equiv := equiv.prod_punit α, continuous_to_fun := continuous_fst, continuous_inv_fun := continuous_id.prod_mk continuous_const }
def
homeomorph.prod_punit
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "continuous_const", "continuous_fst", "equiv.prod_punit" ]
`α × {*}` is homeomorphic to `α`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
punit_prod : punit × α ≃ₜ α
(prod_comm _ _).trans (prod_punit _)
def
homeomorph.punit_prod
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[]
`{*} × α` is homeomorphic to `α`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coe_punit_prod : ⇑(punit_prod α) = prod.snd
rfl
lemma
homeomorph.coe_punit_prod
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
_root_.homeomorph.homeomorph_of_unique [unique α] [unique β] : α ≃ₜ β
{ continuous_to_fun := @continuous_const α β _ _ default, continuous_inv_fun := @continuous_const β α _ _ default, .. equiv.equiv_of_unique α β }
def
homeomorph.homeomorph_of_unique
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "continuous_const", "equiv.equiv_of_unique", "unique" ]
If both `α` and `β` have a unique element, then `α ≃ₜ β`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
Pi_congr_right {ι : Type*} {β₁ β₂ : ι → Type*} [Π i, topological_space (β₁ i)] [Π i, topological_space (β₂ i)] (F : Π i, β₁ i ≃ₜ β₂ i) : (Π i, β₁ i) ≃ₜ (Π i, β₂ i)
{ continuous_to_fun := continuous_pi (λ i, (F i).continuous.comp $ continuous_apply i), continuous_inv_fun := continuous_pi (λ i, (F i).symm.continuous.comp $ continuous_apply i), to_equiv := equiv.Pi_congr_right (λ i, (F i).to_equiv) }
def
homeomorph.Pi_congr_right
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "continuous.comp", "continuous_apply", "continuous_pi", "equiv.Pi_congr_right", "topological_space" ]
If each `β₁ i` is homeomorphic to `β₂ i`, then `Π i, β₁ i` is homeomorphic to `Π i, β₂ i`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
Pi_congr_right_symm {ι : Type*} {β₁ β₂ : ι → Type*} [Π i, topological_space (β₁ i)] [Π i, topological_space (β₂ i)] (F : Π i, β₁ i ≃ₜ β₂ i) : (Pi_congr_right F).symm = Pi_congr_right (λ i, (F i).symm)
rfl
lemma
homeomorph.Pi_congr_right_symm
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "topological_space" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
{u v} ulift {α : Type u} [topological_space α] : ulift.{v u} α ≃ₜ α
{ continuous_to_fun := continuous_ulift_down, continuous_inv_fun := continuous_ulift_up, to_equiv := equiv.ulift }
def
homeomorph.ulift
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "continuous_ulift_down", "continuous_ulift_up", "equiv.ulift", "topological_space" ]
`ulift α` is homeomorphic to `α`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
sum_prod_distrib : (α ⊕ β) × γ ≃ₜ α × γ ⊕ β × γ
homeomorph.symm $ homeomorph_of_continuous_open (equiv.sum_prod_distrib α β γ).symm ((continuous_inl.prod_map continuous_id).sum_elim (continuous_inr.prod_map continuous_id)) $ (is_open_map_inl.prod is_open_map.id).sum_elim (is_open_map_inr.prod is_open_map.id)
def
homeomorph.sum_prod_distrib
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "continuous_id", "equiv.sum_prod_distrib", "homeomorph.symm", "is_open_map.id" ]
`(α ⊕ β) × γ` is homeomorphic to `α × γ ⊕ β × γ`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
prod_sum_distrib : α × (β ⊕ γ) ≃ₜ α × β ⊕ α × γ
(prod_comm _ _).trans $ sum_prod_distrib.trans $ sum_congr (prod_comm _ _) (prod_comm _ _)
def
homeomorph.prod_sum_distrib
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[]
`α × (β ⊕ γ)` is homeomorphic to `α × β ⊕ α × γ`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
sigma_prod_distrib : ((Σ i, σ i) × β) ≃ₜ (Σ i, (σ i × β))
homeomorph.symm $ homeomorph_of_continuous_open (equiv.sigma_prod_distrib σ β).symm (continuous_sigma $ λ i, continuous_sigma_mk.fst'.prod_mk continuous_snd) (is_open_map_sigma.2 $ λ i, is_open_map_sigma_mk.prod is_open_map.id)
def
homeomorph.sigma_prod_distrib
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "continuous_sigma", "continuous_snd", "equiv.sigma_prod_distrib", "homeomorph.symm", "is_open_map.id" ]
`(Σ i, σ i) × β` is homeomorphic to `Σ i, (σ i × β)`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
fun_unique (ι α : Type*) [unique ι] [topological_space α] : (ι → α) ≃ₜ α
{ to_equiv := equiv.fun_unique ι α, continuous_to_fun := continuous_apply _, continuous_inv_fun := continuous_pi (λ _, continuous_id) }
def
homeomorph.fun_unique
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "continuous_apply", "continuous_id", "continuous_pi", "equiv.fun_unique", "topological_space", "unique" ]
If `ι` has a unique element, then `ι → α` is homeomorphic to `α`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
{u} pi_fin_two (α : fin 2 → Type u) [Π i, topological_space (α i)] : (Π i, α i) ≃ₜ α 0 × α 1
{ to_equiv := pi_fin_two_equiv α, continuous_to_fun := (continuous_apply 0).prod_mk (continuous_apply 1), continuous_inv_fun := continuous_pi $ fin.forall_fin_two.2 ⟨continuous_fst, continuous_snd⟩ }
def
homeomorph.pi_fin_two
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "continuous_apply", "continuous_pi", "pi_fin_two_equiv", "topological_space" ]
Homeomorphism between dependent functions `Π i : fin 2, α i` and `α 0 × α 1`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
fin_two_arrow : (fin 2 → α) ≃ₜ α × α
{ to_equiv := fin_two_arrow_equiv α, .. pi_fin_two (λ _, α) }
def
homeomorph.fin_two_arrow
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "fin_two_arrow_equiv" ]
Homeomorphism between `α² = fin 2 → α` and `α × α`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
image (e : α ≃ₜ β) (s : set α) : s ≃ₜ e '' s
{ continuous_to_fun := by continuity!, continuous_inv_fun := by continuity!, to_equiv := e.to_equiv.image s, }
def
homeomorph.image
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[]
A subset of a topological space is homeomorphic to its image under a homeomorphism.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
set.univ (α : Type*) [topological_space α] : (univ : set α) ≃ₜ α
{ to_equiv := equiv.set.univ α, continuous_to_fun := continuous_subtype_coe, continuous_inv_fun := continuous_id.subtype_mk _ }
def
homeomorph.set.univ
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "continuous_subtype_coe", "equiv.set.univ", "topological_space" ]
`set.univ α` is homeomorphic to `α`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
set.prod (s : set α) (t : set β) : ↥(s ×ˢ t) ≃ₜ s × t
{ to_equiv := equiv.set.prod s t, continuous_to_fun := (continuous_subtype_coe.fst.subtype_mk _).prod_mk (continuous_subtype_coe.snd.subtype_mk _), continuous_inv_fun := (continuous_subtype_coe.fst'.prod_mk continuous_subtype_coe.snd').subtype_mk _ }
def
homeomorph.set.prod
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "equiv.set.prod", "set.prod" ]
`s ×ˢ t` is homeomorphic to `s × t`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
pi_equiv_pi_subtype_prod (p : ι → Prop) (β : ι → Type*) [Π i, topological_space (β i)] [decidable_pred p] : (Π i, β i) ≃ₜ (Π i : {x // p x}, β i) × Π i : {x // ¬p x}, β i
{ to_equiv := equiv.pi_equiv_pi_subtype_prod p β, continuous_to_fun := by apply continuous.prod_mk; exact continuous_pi (λ j, continuous_apply j), continuous_inv_fun := continuous_pi $ λ j, begin dsimp only [equiv.pi_equiv_pi_subtype_prod], split_ifs, exacts [(continuous_apply _).comp continuous_fst, (conti...
def
homeomorph.pi_equiv_pi_subtype_prod
topology
src/topology/homeomorph.lean
[ "logic.equiv.fin", "topology.dense_embedding", "topology.support" ]
[ "continuous.prod_mk", "continuous_apply", "continuous_fst", "continuous_pi", "continuous_snd", "equiv.pi_equiv_pi_subtype_prod", "topological_space" ]
The topological space `Π i, β i` can be split as a product by separating the indices in ι depending on whether they satisfy a predicate p or not.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83