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symm_trans_target_eq (e e' : Pretrivialization F proj) : (e.toPartialEquiv.symm.trans e'.toPartialEquiv).target = (e.baseSet ∩ e'.baseSet) ×ˢ univ := by rw [← PartialEquiv.symm_source, symm_trans_symm, symm_trans_source_eq, inter_comm] variable (e' : Pretrivialization F (π F E)) {b : B} {y : E b} @[simp]
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
symm_trans_target_eq
null
coe_mem_source : ↑y ∈ e'.source ↔ b ∈ e'.baseSet := e'.mem_source @[mfld_simps]
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
coe_mem_source
null
coe_coe_fst (hb : b ∈ e'.baseSet) : (e' y).1 = b := by simp [hb]
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
coe_coe_fst
null
mk_mem_target {x : B} {y : F} : (x, y) ∈ e'.target ↔ x ∈ e'.baseSet := e'.mem_target
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
mk_mem_target
null
symm_coe_proj {x : B} {y : F} (e' : Pretrivialization F (π F E)) (h : x ∈ e'.baseSet) : (e'.toPartialEquiv.symm (x, y)).1 = x := e'.proj_symm_apply' h
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
symm_coe_proj
null
protected noncomputable symm (e : Pretrivialization F (π F E)) (b : B) (y : F) : E b := if hb : b ∈ e.baseSet then cast (congr_arg E (e.proj_symm_apply' hb)) (e.toPartialEquiv.symm (b, y)).2 else 0
def
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
symm
A fiberwise inverse to `e`. This is the function `F → E b` that induces a local inverse `B × F → TotalSpace F E` of `e` on `e.baseSet`. It is defined to be `0` outside `e.baseSet`.
symm_apply (e : Pretrivialization F (π F E)) {b : B} (hb : b ∈ e.baseSet) (y : F) : e.symm b y = cast (congr_arg E (e.symm_coe_proj hb)) (e.toPartialEquiv.symm (b, y)).2 := dif_pos hb
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
symm_apply
null
symm_apply_of_notMem (e : Pretrivialization F (π F E)) {b : B} (hb : b ∉ e.baseSet) (y : F) : e.symm b y = 0 := dif_neg hb @[deprecated (since := "2025-05-23")] alias symm_apply_of_not_mem := symm_apply_of_notMem
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
symm_apply_of_notMem
null
coe_symm_of_notMem (e : Pretrivialization F (π F E)) {b : B} (hb : b ∉ e.baseSet) : (e.symm b : F → E b) = 0 := funext fun _ => dif_neg hb @[deprecated (since := "2025-05-23")] alias coe_symm_of_not_mem := coe_symm_of_notMem
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
coe_symm_of_notMem
null
mk_symm (e : Pretrivialization F (π F E)) {b : B} (hb : b ∈ e.baseSet) (y : F) : TotalSpace.mk b (e.symm b y) = e.toPartialEquiv.symm (b, y) := by simp only [e.symm_apply hb, TotalSpace.mk_cast (e.proj_symm_apply' hb), TotalSpace.eta]
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
mk_symm
null
symm_proj_apply (e : Pretrivialization F (π F E)) (z : TotalSpace F E) (hz : z.proj ∈ e.baseSet) : e.symm z.proj (e z).2 = z.2 := by rw [e.symm_apply hz, cast_eq_iff_heq, e.mk_proj_snd' hz, e.symm_apply_apply (e.mem_source.mpr hz)]
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
symm_proj_apply
null
symm_apply_apply_mk (e : Pretrivialization F (π F E)) {b : B} (hb : b ∈ e.baseSet) (y : E b) : e.symm b (e ⟨b, y⟩).2 = y := e.symm_proj_apply ⟨b, y⟩ hb
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
symm_apply_apply_mk
null
apply_mk_symm (e : Pretrivialization F (π F E)) {b : B} (hb : b ∈ e.baseSet) (y : F) : e ⟨b, e.symm b y⟩ = (b, y) := by rw [e.mk_symm hb, e.apply_symm_apply (e.mk_mem_target.mpr hb)]
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
apply_mk_symm
null
Trivialization (proj : Z → B) extends OpenPartialHomeomorph Z (B × F) where baseSet : Set B open_baseSet : IsOpen baseSet source_eq : source = proj ⁻¹' baseSet target_eq : target = baseSet ×ˢ univ proj_toFun : ∀ p ∈ source, (toOpenPartialHomeomorph p).1 = proj p
structure
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
Trivialization
A structure extending open partial homeomorphisms, defining a local trivialization of a projection `proj : Z → B` with fiber `F`, as an open partial homeomorphism between `Z` and `B × F` defined between two sets of the form `proj ⁻¹' baseSet` and `baseSet × F`, acting trivially on the first coordinate.
@[ext] ext' (e e' : Trivialization F proj) (h₁ : e.toOpenPartialHomeomorph = e'.toOpenPartialHomeomorph) (h₂ : e.baseSet = e'.baseSet) : e = e' := by cases e; cases e'; congr
lemma
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
ext'
null
@[coe] toFun' : Z → (B × F) := e.toFun
def
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
toFun'
Coercion of a trivialization to a function. We don't use `e.toFun` in the `CoeFun` instance because it is actually `e.toPartialEquiv.toFun`, so `simp` will apply lemmas about `toPartialEquiv`. While we may want to switch to this behavior later, doing it mid-port will break a lot of proofs.
toPretrivialization : Pretrivialization F proj := { e with }
def
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
toPretrivialization
Natural identification as a `Pretrivialization`.
Simps.apply (proj : Z → B) (e : Trivialization F proj) : Z → B × F := e
def
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
Simps.apply
See Note [custom simps projection]
noncomputable Simps.symm_apply (proj : Z → B) (e : Trivialization F proj) : B × F → Z := e.toOpenPartialHomeomorph.symm initialize_simps_projections Trivialization (toFun → apply, invFun → symm_apply)
def
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
Simps.symm_apply
See Note [custom simps projection]
toPretrivialization_injective : Function.Injective fun e : Trivialization F proj => e.toPretrivialization := fun e e' h => by ext1 exacts [OpenPartialHomeomorph.toPartialEquiv_injective (congr_arg Pretrivialization.toPartialEquiv h), congr_arg Pretrivialization.baseSet h] @[simp, mfld_simps]
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
toPretrivialization_injective
null
coe_coe : ⇑e.toOpenPartialHomeomorph = e := rfl @[simp, mfld_simps]
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
coe_coe
null
coe_fst (ex : x ∈ e.source) : (e x).1 = proj x := e.proj_toFun x ex
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
coe_fst
null
protected eqOn : EqOn (Prod.fst ∘ e) proj e.source := fun _x hx => e.coe_fst hx
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
eqOn
null
mem_source : x ∈ e.source ↔ proj x ∈ e.baseSet := by rw [e.source_eq, mem_preimage]
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
mem_source
null
coe_fst' (ex : proj x ∈ e.baseSet) : (e x).1 = proj x := e.coe_fst (e.mem_source.2 ex)
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
coe_fst'
null
mk_proj_snd (ex : x ∈ e.source) : (proj x, (e x).2) = e x := Prod.ext (e.coe_fst ex).symm rfl
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
mk_proj_snd
null
mk_proj_snd' (ex : proj x ∈ e.baseSet) : (proj x, (e x).2) = e x := Prod.ext (e.coe_fst' ex).symm rfl
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
mk_proj_snd'
null
source_inter_preimage_target_inter (s : Set (B × F)) : e.source ∩ e ⁻¹' (e.target ∩ s) = e.source ∩ e ⁻¹' s := e.toOpenPartialHomeomorph.source_inter_preimage_target_inter s @[simp, mfld_simps]
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
source_inter_preimage_target_inter
null
coe_mk (e : OpenPartialHomeomorph Z (B × F)) (i j k l m) (x : Z) : (Trivialization.mk e i j k l m : Trivialization F proj) x = e x := rfl
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
coe_mk
null
mem_target {x : B × F} : x ∈ e.target ↔ x.1 ∈ e.baseSet := e.toPretrivialization.mem_target
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
mem_target
null
map_target {x : B × F} (hx : x ∈ e.target) : e.toOpenPartialHomeomorph.symm x ∈ e.source := e.toOpenPartialHomeomorph.map_target hx
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
map_target
null
proj_symm_apply {x : B × F} (hx : x ∈ e.target) : proj (e.toOpenPartialHomeomorph.symm x) = x.1 := e.toPretrivialization.proj_symm_apply hx
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
proj_symm_apply
null
proj_symm_apply' {b : B} {x : F} (hx : b ∈ e.baseSet) : proj (e.toOpenPartialHomeomorph.symm (b, x)) = b := e.toPretrivialization.proj_symm_apply' hx
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
proj_symm_apply'
null
proj_surjOn_baseSet [Nonempty F] : Set.SurjOn proj e.source e.baseSet := e.toPretrivialization.proj_surjOn_baseSet
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
proj_surjOn_baseSet
null
apply_symm_apply {x : B × F} (hx : x ∈ e.target) : e (e.toOpenPartialHomeomorph.symm x) = x := e.toOpenPartialHomeomorph.right_inv hx
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
apply_symm_apply
null
apply_symm_apply' {b : B} {x : F} (hx : b ∈ e.baseSet) : e (e.toOpenPartialHomeomorph.symm (b, x)) = (b, x) := e.toPretrivialization.apply_symm_apply' hx @[simp, mfld_simps]
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
apply_symm_apply'
null
symm_apply_mk_proj (ex : x ∈ e.source) : e.toOpenPartialHomeomorph.symm (proj x, (e x).2) = x := e.toPretrivialization.symm_apply_mk_proj ex
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
symm_apply_mk_proj
null
symm_trans_source_eq (e e' : Trivialization F proj) : (e.toPartialEquiv.symm.trans e'.toPartialEquiv).source = (e.baseSet ∩ e'.baseSet) ×ˢ univ := Pretrivialization.symm_trans_source_eq e.toPretrivialization e'
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
symm_trans_source_eq
null
symm_trans_target_eq (e e' : Trivialization F proj) : (e.toPartialEquiv.symm.trans e'.toPartialEquiv).target = (e.baseSet ∩ e'.baseSet) ×ˢ univ := Pretrivialization.symm_trans_target_eq e.toPretrivialization e'
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
symm_trans_target_eq
null
coe_fst_eventuallyEq_proj (ex : x ∈ e.source) : Prod.fst ∘ e =ᶠ[𝓝 x] proj := mem_nhds_iff.2 ⟨e.source, fun _y hy => e.coe_fst hy, e.open_source, ex⟩
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
coe_fst_eventuallyEq_proj
null
coe_fst_eventuallyEq_proj' (ex : proj x ∈ e.baseSet) : Prod.fst ∘ e =ᶠ[𝓝 x] proj := e.coe_fst_eventuallyEq_proj (e.mem_source.2 ex)
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
coe_fst_eventuallyEq_proj'
null
map_proj_nhds (ex : x ∈ e.source) : map proj (𝓝 x) = 𝓝 (proj x) := by rw [← e.coe_fst ex, ← map_congr (e.coe_fst_eventuallyEq_proj ex), ← map_map, ← e.coe_coe, e.map_nhds_eq ex, map_fst_nhds]
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
map_proj_nhds
null
preimage_subset_source {s : Set B} (hb : s ⊆ e.baseSet) : proj ⁻¹' s ⊆ e.source := fun _p hp => e.mem_source.mpr (hb hp)
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
preimage_subset_source
null
image_preimage_eq_prod_univ {s : Set B} (hb : s ⊆ e.baseSet) : e '' (proj ⁻¹' s) = s ×ˢ univ := Subset.antisymm (image_subset_iff.mpr fun p hp => ⟨(e.proj_toFun p (e.preimage_subset_source hb hp)).symm ▸ hp, trivial⟩) fun p hp => let hp' : p ∈ e.target := e.mem_target.mpr (hb hp.1) ⟨e.invFun p, mem_preimage.mpr ((e.proj_symm_apply hp').symm ▸ hp.1), e.apply_symm_apply hp'⟩
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
image_preimage_eq_prod_univ
null
tendsto_nhds_iff {α : Type*} {l : Filter α} {f : α → Z} {z : Z} (hz : z ∈ e.source) : Tendsto f l (𝓝 z) ↔ Tendsto (proj ∘ f) l (𝓝 (proj z)) ∧ Tendsto (fun x ↦ (e (f x)).2) l (𝓝 (e z).2) := by rw [e.nhds_eq_comap_inf_principal hz, tendsto_inf, tendsto_comap_iff, Prod.tendsto_iff, coe_coe, tendsto_principal, coe_fst _ hz] by_cases hl : ∀ᶠ x in l, f x ∈ e.source · simp only [hl, and_true] refine (tendsto_congr' ?_).and Iff.rfl exact hl.mono fun x ↦ e.coe_fst · simp only [hl, and_false, false_iff, not_and] rw [e.source_eq] at hl hz exact fun h _ ↦ hl <| h <| e.open_baseSet.mem_nhds hz
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
tendsto_nhds_iff
null
nhds_eq_inf_comap {z : Z} (hz : z ∈ e.source) : 𝓝 z = comap proj (𝓝 (proj z)) ⊓ comap (Prod.snd ∘ e) (𝓝 (e z).2) := by refine eq_of_forall_le_iff fun l ↦ ?_ rw [le_inf_iff, ← tendsto_iff_comap, ← tendsto_iff_comap] exact e.tendsto_nhds_iff hz
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
nhds_eq_inf_comap
null
preimageHomeomorph {s : Set B} (hb : s ⊆ e.baseSet) : proj ⁻¹' s ≃ₜ s × F := (e.toOpenPartialHomeomorph.homeomorphOfImageSubsetSource (e.preimage_subset_source hb) (e.image_preimage_eq_prod_univ hb)).trans ((Homeomorph.Set.prod s univ).trans ((Homeomorph.refl s).prodCongr (Homeomorph.Set.univ F))) @[simp]
def
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
preimageHomeomorph
The preimage of a subset of the base set is homeomorphic to the product with the fiber.
preimageHomeomorph_apply {s : Set B} (hb : s ⊆ e.baseSet) (p : proj ⁻¹' s) : e.preimageHomeomorph hb p = (⟨proj p, p.2⟩, (e p).2) := Prod.ext (Subtype.ext (e.proj_toFun p (e.mem_source.mpr (hb p.2)))) rfl
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
preimageHomeomorph_apply
null
protected preimageHomeomorph_symm_apply.aux {s : Set B} (hb : s ⊆ e.baseSet) := (e.preimageHomeomorph hb).symm @[simp]
def
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
preimageHomeomorph_symm_apply.aux
Auxiliary definition to avoid looping in `dsimp` with `Trivialization.preimageHomeomorph_symm_apply`.
preimageHomeomorph_symm_apply {s : Set B} (hb : s ⊆ e.baseSet) (p : s × F) : (e.preimageHomeomorph hb).symm p = ⟨e.symm (p.1, p.2), ((preimageHomeomorph_symm_apply.aux e hb) p).2⟩ := rfl
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
preimageHomeomorph_symm_apply
null
sourceHomeomorphBaseSetProd : e.source ≃ₜ e.baseSet × F := (Homeomorph.setCongr e.source_eq).trans (e.preimageHomeomorph subset_rfl) @[simp]
def
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
sourceHomeomorphBaseSetProd
The source is homeomorphic to the product of the base set with the fiber.
sourceHomeomorphBaseSetProd_apply (p : e.source) : e.sourceHomeomorphBaseSetProd p = (⟨proj p, e.mem_source.mp p.2⟩, (e p).2) := e.preimageHomeomorph_apply subset_rfl ⟨p, e.mem_source.mp p.2⟩
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
sourceHomeomorphBaseSetProd_apply
null
protected sourceHomeomorphBaseSetProd_symm_apply.aux := e.sourceHomeomorphBaseSetProd.symm @[simp]
def
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
sourceHomeomorphBaseSetProd_symm_apply.aux
Auxiliary definition to avoid looping in `dsimp` with `Trivialization.sourceHomeomorphBaseSetProd_symm_apply`.
sourceHomeomorphBaseSetProd_symm_apply (p : e.baseSet × F) : e.sourceHomeomorphBaseSetProd.symm p = ⟨e.symm (p.1, p.2), (sourceHomeomorphBaseSetProd_symm_apply.aux e p).2⟩ := rfl
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
sourceHomeomorphBaseSetProd_symm_apply
null
preimageSingletonHomeomorph {b : B} (hb : b ∈ e.baseSet) : proj ⁻¹' {b} ≃ₜ F := .trans (e.preimageHomeomorph (Set.singleton_subset_iff.mpr hb)) <| .trans (.prodCongr (Homeomorph.homeomorphOfUnique ({b} : Set B) PUnit.{1}) (Homeomorph.refl F)) (Homeomorph.punitProd F) @[simp]
def
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
preimageSingletonHomeomorph
Each fiber of a trivialization is homeomorphic to the specified fiber.
preimageSingletonHomeomorph_apply {b : B} (hb : b ∈ e.baseSet) (p : proj ⁻¹' {b}) : e.preimageSingletonHomeomorph hb p = (e p).2 := rfl @[simp]
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
preimageSingletonHomeomorph_apply
null
preimageSingletonHomeomorph_symm_apply {b : B} (hb : b ∈ e.baseSet) (p : F) : (e.preimageSingletonHomeomorph hb).symm p = ⟨e.symm (b, p), by rw [mem_preimage, e.proj_symm_apply' hb, mem_singleton_iff]⟩ := rfl
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
preimageSingletonHomeomorph_symm_apply
null
continuousAt_proj (ex : x ∈ e.source) : ContinuousAt proj x := (e.map_proj_nhds ex).le
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
continuousAt_proj
In the domain of a bundle trivialization, the projection is continuous
continuousOn_proj : ContinuousOn proj e.source := continuousOn_of_forall_continuousAt fun _ ↦ e.continuousAt_proj
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
continuousOn_proj
null
protected compHomeomorph {Z' : Type*} [TopologicalSpace Z'] (h : Z' ≃ₜ Z) : Trivialization F (proj ∘ h) where toOpenPartialHomeomorph := h.toOpenPartialHomeomorph.trans e.toOpenPartialHomeomorph baseSet := e.baseSet open_baseSet := e.open_baseSet source_eq := by simp [source_eq, preimage_preimage, Function.comp_def] target_eq := by simp [target_eq] proj_toFun p hp := by have hp : h p ∈ e.source := by simpa using hp simp [hp]
def
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
compHomeomorph
Composition of a `Trivialization` and a `Homeomorph`.
continuousAt_of_comp_right {X : Type*} [TopologicalSpace X] {f : Z → X} {z : Z} (e : Trivialization F proj) (he : proj z ∈ e.baseSet) (hf : ContinuousAt (f ∘ e.toPartialEquiv.symm) (e z)) : ContinuousAt f z := by have hez : z ∈ e.toPartialEquiv.symm.target := by rw [PartialEquiv.symm_target, e.mem_source] exact he rwa [e.toOpenPartialHomeomorph.symm.continuousAt_iff_continuousAt_comp_right hez, OpenPartialHomeomorph.symm_symm]
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
continuousAt_of_comp_right
Read off the continuity of a function `f : Z → X` at `z : Z` by transferring via a trivialization of `Z` containing `z`.
continuousAt_of_comp_left {X : Type*} [TopologicalSpace X] {f : X → Z} {x : X} (e : Trivialization F proj) (hf_proj : ContinuousAt (proj ∘ f) x) (he : proj (f x) ∈ e.baseSet) (hf : ContinuousAt (e ∘ f) x) : ContinuousAt f x := by rw [e.continuousAt_iff_continuousAt_comp_left] · exact hf rw [e.source_eq, ← preimage_comp] exact hf_proj.preimage_mem_nhds (e.open_baseSet.mem_nhds he) variable (e' : Trivialization F (π F E)) {b : B} {y : E b}
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
continuousAt_of_comp_left
Read off the continuity of a function `f : X → Z` at `x : X` by transferring via a trivialization of `Z` containing `f x`.
protected continuousOn : ContinuousOn e' e'.source := e'.continuousOn_toFun
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
continuousOn
null
coe_mem_source : ↑y ∈ e'.source ↔ b ∈ e'.baseSet := e'.mem_source @[simp, mfld_simps]
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
coe_mem_source
null
coe_coe_fst (hb : b ∈ e'.baseSet) : (e' y).1 = b := e'.coe_fst (e'.mem_source.2 hb)
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
coe_coe_fst
null
mk_mem_target {y : F} : (b, y) ∈ e'.target ↔ b ∈ e'.baseSet := e'.toPretrivialization.mem_target
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
mk_mem_target
null
symm_apply_apply {x : TotalSpace F E} (hx : x ∈ e'.source) : e'.toOpenPartialHomeomorph.symm (e' x) = x := e'.toPartialEquiv.left_inv hx @[simp, mfld_simps]
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
symm_apply_apply
null
symm_coe_proj {x : B} {y : F} (e : Trivialization F (π F E)) (h : x ∈ e.baseSet) : (e.toOpenPartialHomeomorph.symm (x, y)).1 = x := e.proj_symm_apply' h
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
symm_coe_proj
null
protected noncomputable symm (e : Trivialization F (π F E)) (b : B) (y : F) : E b := e.toPretrivialization.symm b y
def
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
symm
A fiberwise inverse to `e'`. The function `F → E x` that induces a local inverse `B × F → TotalSpace F E` of `e'` on `e'.baseSet`. It is defined to be `0` outside `e'.baseSet`.
symm_apply (e : Trivialization F (π F E)) {b : B} (hb : b ∈ e.baseSet) (y : F) : e.symm b y = cast (congr_arg E (e.symm_coe_proj hb)) (e.toOpenPartialHomeomorph.symm (b, y)).2 := dif_pos hb
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
symm_apply
null
symm_apply_of_notMem (e : Trivialization F (π F E)) {b : B} (hb : b ∉ e.baseSet) (y : F) : e.symm b y = 0 := dif_neg hb @[deprecated (since := "2025-05-23")] alias symm_apply_of_not_mem := symm_apply_of_notMem
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
symm_apply_of_notMem
null
mk_symm (e : Trivialization F (π F E)) {b : B} (hb : b ∈ e.baseSet) (y : F) : TotalSpace.mk b (e.symm b y) = e.toOpenPartialHomeomorph.symm (b, y) := e.toPretrivialization.mk_symm hb y
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
mk_symm
null
symm_proj_apply (e : Trivialization F (π F E)) (z : TotalSpace F E) (hz : z.proj ∈ e.baseSet) : e.symm z.proj (e z).2 = z.2 := e.toPretrivialization.symm_proj_apply z hz
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
symm_proj_apply
null
symm_apply_apply_mk (e : Trivialization F (π F E)) {b : B} (hb : b ∈ e.baseSet) (y : E b) : e.symm b (e ⟨b, y⟩).2 = y := e.symm_proj_apply ⟨b, y⟩ hb
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
symm_apply_apply_mk
null
apply_mk_symm (e : Trivialization F (π F E)) {b : B} (hb : b ∈ e.baseSet) (y : F) : e ⟨b, e.symm b y⟩ = (b, y) := e.toPretrivialization.apply_mk_symm hb y
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
apply_mk_symm
null
continuousOn_symm (e : Trivialization F (π F E)) : ContinuousOn (fun z : B × F => TotalSpace.mk' F z.1 (e.symm z.1 z.2)) (e.baseSet ×ˢ univ) := by have : ∀ z ∈ e.baseSet ×ˢ (univ : Set F), TotalSpace.mk z.1 (e.symm z.1 z.2) = e.toOpenPartialHomeomorph.symm z := by rintro x ⟨hx : x.1 ∈ e.baseSet, _⟩ rw [e.mk_symm hx] refine ContinuousOn.congr ?_ this rw [← e.target_eq] exact e.toOpenPartialHomeomorph.continuousOn_symm
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
continuousOn_symm
null
transFiberHomeomorph {F' : Type*} [TopologicalSpace F'] (e : Trivialization F proj) (h : F ≃ₜ F') : Trivialization F' proj where toOpenPartialHomeomorph := e.toOpenPartialHomeomorph.transHomeomorph <| (Homeomorph.refl _).prodCongr h baseSet := e.baseSet open_baseSet := e.open_baseSet source_eq := e.source_eq target_eq := by simp [target_eq, prod_univ, preimage_preimage] proj_toFun := e.proj_toFun @[simp]
def
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
transFiberHomeomorph
If `e` is a `Trivialization` of `proj : Z → B` with fiber `F` and `h` is a homeomorphism `F ≃ₜ F'`, then `e.trans_fiber_homeomorph h` is the trivialization of `proj` with the fiber `F'` that sends `p : Z` to `((e p).1, h (e p).2)`.
transFiberHomeomorph_apply {F' : Type*} [TopologicalSpace F'] (e : Trivialization F proj) (h : F ≃ₜ F') (x : Z) : e.transFiberHomeomorph h x = ((e x).1, h (e x).2) := rfl
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
transFiberHomeomorph_apply
null
coordChange (e₁ e₂ : Trivialization F proj) (b : B) (x : F) : F := (e₂ <| e₁.toOpenPartialHomeomorph.symm (b, x)).2
def
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
coordChange
Coordinate transformation in the fiber induced by a pair of bundle trivializations. See also `Trivialization.coordChangeHomeomorph` for a version bundled as `F ≃ₜ F`.
mk_coordChange (e₁ e₂ : Trivialization F proj) {b : B} (h₁ : b ∈ e₁.baseSet) (h₂ : b ∈ e₂.baseSet) (x : F) : (b, e₁.coordChange e₂ b x) = e₂ (e₁.toOpenPartialHomeomorph.symm (b, x)) := by refine Prod.ext ?_ rfl rw [e₂.coe_fst', ← e₁.coe_fst', e₁.apply_symm_apply' h₁] · rwa [e₁.proj_symm_apply' h₁] · rwa [e₁.proj_symm_apply' h₁]
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
mk_coordChange
null
coordChange_apply_snd (e₁ e₂ : Trivialization F proj) {p : Z} (h : proj p ∈ e₁.baseSet) : e₁.coordChange e₂ (proj p) (e₁ p).snd = (e₂ p).snd := by rw [coordChange, e₁.symm_apply_mk_proj (e₁.mem_source.2 h)]
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
coordChange_apply_snd
null
coordChange_same_apply (e : Trivialization F proj) {b : B} (h : b ∈ e.baseSet) (x : F) : e.coordChange e b x = x := by rw [coordChange, e.apply_symm_apply' h]
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
coordChange_same_apply
null
coordChange_same (e : Trivialization F proj) {b : B} (h : b ∈ e.baseSet) : e.coordChange e b = id := funext <| e.coordChange_same_apply h
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
coordChange_same
null
coordChange_coordChange (e₁ e₂ e₃ : Trivialization F proj) {b : B} (h₁ : b ∈ e₁.baseSet) (h₂ : b ∈ e₂.baseSet) (x : F) : e₂.coordChange e₃ b (e₁.coordChange e₂ b x) = e₁.coordChange e₃ b x := by rw [coordChange, e₁.mk_coordChange _ h₁ h₂, ← e₂.coe_coe, e₂.left_inv, coordChange] rwa [e₂.mem_source, e₁.proj_symm_apply' h₁]
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
coordChange_coordChange
null
continuous_coordChange (e₁ e₂ : Trivialization F proj) {b : B} (h₁ : b ∈ e₁.baseSet) (h₂ : b ∈ e₂.baseSet) : Continuous (e₁.coordChange e₂ b) := by refine continuous_snd.comp (e₂.toOpenPartialHomeomorph.continuousOn.comp_continuous (e₁.toOpenPartialHomeomorph.continuousOn_symm.comp_continuous ?_ ?_) ?_) · fun_prop · exact fun x => e₁.mem_target.2 h₁ · intro x rwa [e₂.mem_source, e₁.proj_symm_apply' h₁]
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
continuous_coordChange
null
protected coordChangeHomeomorph (e₁ e₂ : Trivialization F proj) {b : B} (h₁ : b ∈ e₁.baseSet) (h₂ : b ∈ e₂.baseSet) : F ≃ₜ F where toFun := e₁.coordChange e₂ b invFun := e₂.coordChange e₁ b left_inv x := by simp only [*, coordChange_coordChange, coordChange_same_apply] right_inv x := by simp only [*, coordChange_coordChange, coordChange_same_apply] continuous_toFun := e₁.continuous_coordChange e₂ h₁ h₂ continuous_invFun := e₂.continuous_coordChange e₁ h₂ h₁ @[simp]
def
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
coordChangeHomeomorph
Coordinate transformation in the fiber induced by a pair of bundle trivializations, as a homeomorphism.
coordChangeHomeomorph_coe (e₁ e₂ : Trivialization F proj) {b : B} (h₁ : b ∈ e₁.baseSet) (h₂ : b ∈ e₂.baseSet) : ⇑(e₁.coordChangeHomeomorph e₂ h₁ h₂) = e₁.coordChange e₂ b := rfl
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
coordChangeHomeomorph_coe
null
isImage_preimage_prod (e : Trivialization F proj) (s : Set B) : e.toOpenPartialHomeomorph.IsImage (proj ⁻¹' s) (s ×ˢ univ) := fun x hx => by simp [hx]
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
isImage_preimage_prod
null
protected restrOpen (e : Trivialization F proj) (s : Set B) (hs : IsOpen s) : Trivialization F proj where toOpenPartialHomeomorph := ((e.isImage_preimage_prod s).symm.restr (IsOpen.inter e.open_target (hs.prod isOpen_univ))).symm baseSet := e.baseSet ∩ s open_baseSet := IsOpen.inter e.open_baseSet hs source_eq := by simp [source_eq] target_eq := by simp [target_eq, prod_univ] proj_toFun p hp := e.proj_toFun p hp.1
def
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
restrOpen
Restrict a `Trivialization` to an open set in the base.
frontier_preimage (e : Trivialization F proj) (s : Set B) : e.source ∩ frontier (proj ⁻¹' s) = proj ⁻¹' (e.baseSet ∩ frontier s) := by rw [← (e.isImage_preimage_prod s).frontier.preimage_eq, frontier_prod_univ_eq, (e.isImage_preimage_prod _).preimage_eq, e.source_eq, preimage_inter] open Classical in
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
frontier_preimage
null
noncomputable piecewise (e e' : Trivialization F proj) (s : Set B) (Hs : e.baseSet ∩ frontier s = e'.baseSet ∩ frontier s) (Heq : EqOn e e' <| proj ⁻¹' (e.baseSet ∩ frontier s)) : Trivialization F proj where toOpenPartialHomeomorph := e.toOpenPartialHomeomorph.piecewise e'.toOpenPartialHomeomorph (proj ⁻¹' s) (s ×ˢ univ) (e.isImage_preimage_prod s) (e'.isImage_preimage_prod s) (by rw [e.frontier_preimage, e'.frontier_preimage, Hs]) (by rwa [e.frontier_preimage]) baseSet := s.ite e.baseSet e'.baseSet open_baseSet := e.open_baseSet.ite e'.open_baseSet Hs source_eq := by simp [source_eq] target_eq := by simp [target_eq, prod_univ] proj_toFun p := by rintro (⟨he, hs⟩ | ⟨he, hs⟩) <;> simp [*]
def
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
piecewise
Given two bundle trivializations `e`, `e'` of `proj : Z → B` and a set `s : Set B` such that the base sets of `e` and `e'` intersect `frontier s` on the same set and `e p = e' p` whenever `proj p ∈ e.baseSet ∩ frontier s`, `e.piecewise e' s Hs Heq` is the bundle trivialization over `Set.ite s e.baseSet e'.baseSet` that is equal to `e` on `proj ⁻¹ s` and is equal to `e'` otherwise.
noncomputable piecewiseLeOfEq [LinearOrder B] [OrderTopology B] (e e' : Trivialization F proj) (a : B) (He : a ∈ e.baseSet) (He' : a ∈ e'.baseSet) (Heq : ∀ p, proj p = a → e p = e' p) : Trivialization F proj := e.piecewise e' (Iic a) (Set.ext fun x => and_congr_left_iff.2 fun hx => by obtain rfl : x = a := mem_singleton_iff.1 (frontier_Iic_subset _ hx) simp [He, He']) fun p hp => Heq p <| frontier_Iic_subset _ hp.2
def
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
piecewiseLeOfEq
Given two bundle trivializations `e`, `e'` of a topological fiber bundle `proj : Z → B` over a linearly ordered base `B` and a point `a ∈ e.baseSet ∩ e'.baseSet` such that `e` equals `e'` on `proj ⁻¹' {a}`, `e.piecewise_le_of_eq e' a He He' Heq` is the bundle trivialization over `Set.ite (Iic a) e.baseSet e'.baseSet` that is equal to `e` on points `p` such that `proj p ≤ a` and is equal to `e'` otherwise.
noncomputable piecewiseLe [LinearOrder B] [OrderTopology B] (e e' : Trivialization F proj) (a : B) (He : a ∈ e.baseSet) (He' : a ∈ e'.baseSet) : Trivialization F proj := e.piecewiseLeOfEq (e'.transFiberHomeomorph (e'.coordChangeHomeomorph e He' He)) a He He' <| by rintro p rfl ext1 · simp [e.coe_fst', e'.coe_fst', *] · simp [coordChange_apply_snd, *] open Classical in
def
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
piecewiseLe
Given two bundle trivializations `e`, `e'` of a topological fiber bundle `proj : Z → B` over a linearly ordered base `B` and a point `a ∈ e.baseSet ∩ e'.baseSet`, `e.piecewise_le e' a He He'` is the bundle trivialization over `Set.ite (Iic a) e.baseSet e'.baseSet` that is equal to `e` on points `p` such that `proj p ≤ a` and is equal to `((e' p).1, h (e' p).2)` otherwise, where `h = e'.coord_change_homeomorph e _ _` is the homeomorphism of the fiber such that `h (e' p).2 = (e p).2` whenever `e p = a`.
noncomputable disjointUnion (e e' : Trivialization F proj) (H : Disjoint e.baseSet e'.baseSet) : Trivialization F proj where toOpenPartialHomeomorph := e.toOpenPartialHomeomorph.disjointUnion e'.toOpenPartialHomeomorph (by rw [e.source_eq, e'.source_eq] exact H.preimage _) (by rw [e.target_eq, e'.target_eq, disjoint_iff_inf_le] intro x hx exact H.le_bot ⟨hx.1.1, hx.2.1⟩) baseSet := e.baseSet ∪ e'.baseSet open_baseSet := IsOpen.union e.open_baseSet e'.open_baseSet source_eq := congr_arg₂ (· ∪ ·) e.source_eq e'.source_eq target_eq := (congr_arg₂ (· ∪ ·) e.target_eq e'.target_eq).trans union_prod.symm proj_toFun := by rintro p (hp | hp') · change (e.source.piecewise e e' p).1 = proj p rw [piecewise_eq_of_mem, e.coe_fst] <;> exact hp · change (e.source.piecewise e e' p).1 = proj p rw [piecewise_eq_of_notMem, e'.coe_fst hp'] simp only [source_eq] at hp' ⊢ exact fun h => H.le_bot ⟨h, hp'⟩
def
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
disjointUnion
Given two bundle trivializations `e`, `e'` over disjoint sets, `e.disjoint_union e' H` is the bundle trivialization over the union of the base sets that agrees with `e` and `e'` over their base sets.
lift (T : Trivialization F proj) (z : Z) (b : B) : Z := T.invFun (b, (T z).2) variable {T : Trivialization F proj} {z : Z} {b : B} @[simp]
def
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
lift
The local lifting through a Trivialization `T` from the base to the leaf containing `z`.
lift_self (he : proj z ∈ T.baseSet) : T.lift z (proj z) = z := symm_apply_mk_proj _ <| T.mem_source.2 he
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
lift_self
null
proj_lift (hx : b ∈ T.baseSet) : proj (T.lift z b) = b := T.proj_symm_apply <| T.mem_target.2 hx
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
proj_lift
null
liftCM (T : Trivialization F proj) : C(T.source × T.baseSet, T.source) where toFun ex := ⟨T.lift ex.1 ex.2, T.map_target (by simp [mem_target])⟩ continuous_toFun := by apply Continuous.subtype_mk refine T.continuousOn_invFun.comp_continuous ?_ (by simp [mem_target]) refine .prodMk (by fun_prop) (.snd ?_) exact T.continuousOn_toFun.comp_continuous (by fun_prop) (by simp) variable {ι : Type*} [TopologicalSpace ι] [LocallyCompactPair ι T.baseSet] {γ : C(ι, T.baseSet)} {i : ι} {e : T.source}
def
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
liftCM
The restriction of `lift` to the source and base set of `T`, as a bundled continuous map.
clift (T : Trivialization F proj) [LocallyCompactPair ι T.baseSet] : C(T.source × C(ι, T.baseSet), C(ι, T.source)) := by let Ψ : C((T.source × C(ι, T.baseSet)) × ι, C(ι, T.baseSet) × ι) := ⟨fun eγt => (eγt.1.2, eγt.2), by fun_prop⟩ refine ContinuousMap.curry <| T.liftCM.comp <| ⟨fun eγt => ⟨eγt.1.1, eγt.1.2 eγt.2⟩, ?_⟩ simpa using ⟨by fun_prop, ContinuousEval.continuous_eval.comp Ψ.continuous⟩ @[simp]
def
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
clift
Extension of `liftCM` to continuous maps taking values in `T.baseSet` (local version of homotopy lifting)
clift_self (h : proj e.1 = γ i) : T.clift (e, γ) i = e := by have : proj e ∈ T.baseSet := by simp [h] simp [clift, liftCM, ← h, lift_self, this]
theorem
Topology
[ "Mathlib.Data.Bundle", "Mathlib.Data.Set.Image", "Mathlib.Topology.CompactOpen", "Mathlib.Topology.OpenPartialHomeomorph", "Mathlib.Topology.Order.Basic" ]
Mathlib/Topology/FiberBundle/Trivialization.lean
clift_self
null