statement
stringlengths
1
2.88k
proof
stringlengths
0
13.9k
type
stringclasses
10 values
symbolic_name
stringlengths
1
131
library
stringclasses
417 values
filename
stringlengths
17
80
imports
listlengths
0
16
deps
listlengths
0
64
docstring
stringlengths
0
10.2k
source_url
stringclasses
1 value
commit
stringclasses
1 value
conj_invariant_subalgebra (A : subalgebra ℝ C(X, 𝕜)) : Prop
A.map (conj_ae.to_alg_hom.comp_left_continuous ℝ conj_cle.continuous) ≤ A
def
continuous_map.conj_invariant_subalgebra
topology.continuous_function
src/topology/continuous_function/stone_weierstrass.lean
[ "topology.continuous_function.weierstrass", "data.is_R_or_C.basic" ]
[ "subalgebra" ]
A real subalgebra of `C(X, 𝕜)` is `conj_invariant`, if it contains all its conjugates.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mem_conj_invariant_subalgebra {A : subalgebra ℝ C(X, 𝕜)} (hA : conj_invariant_subalgebra A) {f : C(X, 𝕜)} (hf : f ∈ A) : (conj_ae.to_alg_hom.comp_left_continuous ℝ conj_cle.continuous) f ∈ A
hA ⟨f, hf, rfl⟩
lemma
continuous_map.mem_conj_invariant_subalgebra
topology.continuous_function
src/topology/continuous_function/stone_weierstrass.lean
[ "topology.continuous_function.weierstrass", "data.is_R_or_C.basic" ]
[ "subalgebra" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
subalgebra_conj_invariant {S : set C(X, 𝕜)} (hS : ∀ f, f ∈ S → (conj_ae.to_alg_hom.comp_left_continuous ℝ conj_cle.continuous) f ∈ S) : conj_invariant_subalgebra ((algebra.adjoin 𝕜 S).restrict_scalars ℝ)
begin rintros _ ⟨f, hf, rfl⟩, change _ ∈ ((algebra.adjoin 𝕜 S).restrict_scalars ℝ), change _ ∈ ((algebra.adjoin 𝕜 S).restrict_scalars ℝ) at hf, rw subalgebra.mem_restrict_scalars at hf ⊢, apply algebra.adjoin_induction hf, { exact λ g hg, algebra.subset_adjoin (hS g hg), }, { exact λ c, subalgebra.algeb...
lemma
continuous_map.subalgebra_conj_invariant
topology.continuous_function
src/topology/continuous_function/stone_weierstrass.lean
[ "topology.continuous_function.weierstrass", "data.is_R_or_C.basic" ]
[ "alg_hom.map_add", "alg_hom.map_mul", "algebra.adjoin", "algebra.adjoin_induction", "algebra.subset_adjoin", "restrict_scalars", "star_ring_end", "subalgebra.add_mem", "subalgebra.algebra_map_mem", "subalgebra.mem_restrict_scalars", "subalgebra.mul_mem" ]
If a set `S` is conjugation-invariant, then its `𝕜`-span is conjugation-invariant.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
subalgebra.separates_points.is_R_or_C_to_real {A : subalgebra 𝕜 C(X, 𝕜)} (hA : A.separates_points) (hA' : conj_invariant_subalgebra (A.restrict_scalars ℝ)) : ((A.restrict_scalars ℝ).comap (of_real_am.comp_left_continuous ℝ continuous_of_real)).separates_points
begin intros x₁ x₂ hx, -- Let `f` in the subalgebra `A` separate the points `x₁`, `x₂` obtain ⟨_, ⟨f, hfA, rfl⟩, hf⟩ := hA hx, let F : C(X, 𝕜) := f - const _ (f x₂), -- Subtract the constant `f x₂` from `f`; this is still an element of the subalgebra have hFA : F ∈ A, { refine A.sub_mem hfA (@eq.subst _ ...
lemma
subalgebra.separates_points.is_R_or_C_to_real
topology.continuous_function
src/topology/continuous_function/stone_weierstrass.lean
[ "topology.continuous_function.weierstrass", "data.is_R_or_C.basic" ]
[ "algebra.id.smul_eq_mul", "is_R_or_C.mul_conj", "mul_comm", "mul_one", "pi.one_apply", "pi.smul_apply", "set_like.mem_coe", "subalgebra", "subalgebra.mem_comap" ]
If a conjugation-invariant subalgebra of `C(X, 𝕜)` separates points, then the real subalgebra of its purely real-valued elements also separates points.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
continuous_map.subalgebra_is_R_or_C_topological_closure_eq_top_of_separates_points (A : subalgebra 𝕜 C(X, 𝕜)) (hA : A.separates_points) (hA' : conj_invariant_subalgebra (A.restrict_scalars ℝ)) : A.topological_closure = ⊤
begin rw algebra.eq_top_iff, -- Let `I` be the natural inclusion of `C(X, ℝ)` into `C(X, 𝕜)` let I : C(X, ℝ) →ₗ[ℝ] C(X, 𝕜) := of_real_clm.comp_left_continuous ℝ X, -- The main point of the proof is that its range (i.e., every real-valued function) is contained -- in the closure of `A` have key : I.range ≤...
theorem
continuous_map.subalgebra_is_R_or_C_topological_closure_eq_top_of_separates_points
topology.continuous_function
src/topology/continuous_function/stone_weierstrass.lean
[ "topology.continuous_function.weierstrass", "data.is_R_or_C.basic" ]
[ "algebra.eq_top_iff", "mul_comm", "subalgebra", "subalgebra.to_submodule", "submodule", "submodule.map_top", "submodule.topological_closure_mono" ]
The Stone-Weierstrass approximation theorem, `is_R_or_C` version, that a subalgebra `A` of `C(X, 𝕜)`, where `X` is a compact topological space and `is_R_or_C 𝕜`, is dense if it is conjugation-invariant and separates points.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
eq_induced_by_maps_to_sierpinski (X : Type*) [t : topological_space X] : t = ⨅ (u : opens X), sierpinski_space.induced (∈ u)
begin apply le_antisymm, { rw [le_infi_iff], exact λ u, continuous.le_induced (is_open_iff_continuous_mem.mp u.2) }, { intros u h, rw ← generate_from_Union_is_open, apply is_open_generate_from_of_mem, simp only [set.mem_Union, set.mem_set_of_eq, is_open_induced_iff], exact ⟨⟨u, h⟩, {true}, is_...
lemma
topological_space.eq_induced_by_maps_to_sierpinski
topology.continuous_function
src/topology/continuous_function/t0_sierpinski.lean
[ "topology.order", "topology.sets.opens", "topology.continuous_function.basic" ]
[ "continuous.le_induced", "generate_from_Union_is_open", "is_open_induced_iff", "is_open_singleton_true", "le_infi_iff", "set.mem_Union", "set.preimage", "topological_space" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
product_of_mem_opens : C(X, opens X → Prop)
{ to_fun := λ x u, x ∈ u, continuous_to_fun := continuous_pi_iff.2 (λ u, continuous_Prop.2 u.is_open) }
def
topological_space.product_of_mem_opens
topology.continuous_function
src/topology/continuous_function/t0_sierpinski.lean
[ "topology.order", "topology.sets.opens", "topology.continuous_function.basic" ]
[]
The continuous map from `X` to the product of copies of the Sierpinski space, (one copy for each open subset `u` of `X`). The `u` coordinate of `product_of_mem_opens x` is given by `x ∈ u`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
product_of_mem_opens_inducing : inducing (product_of_mem_opens X)
begin convert inducing_infi_to_pi (λ (u : opens X) (x : X), x ∈ u), apply eq_induced_by_maps_to_sierpinski, end
lemma
topological_space.product_of_mem_opens_inducing
topology.continuous_function
src/topology/continuous_function/t0_sierpinski.lean
[ "topology.order", "topology.sets.opens", "topology.continuous_function.basic" ]
[ "inducing", "inducing_infi_to_pi" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
product_of_mem_opens_injective [t0_space X] : function.injective (product_of_mem_opens X)
begin intros x1 x2 h, apply inseparable.eq, rw [←inducing.inseparable_iff (product_of_mem_opens_inducing X), h], end
lemma
topological_space.product_of_mem_opens_injective
topology.continuous_function
src/topology/continuous_function/t0_sierpinski.lean
[ "topology.order", "topology.sets.opens", "topology.continuous_function.basic" ]
[ "inseparable.eq", "t0_space" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
product_of_mem_opens_embedding [t0_space X] : embedding (product_of_mem_opens X)
embedding.mk (product_of_mem_opens_inducing X) (product_of_mem_opens_injective X)
theorem
topological_space.product_of_mem_opens_embedding
topology.continuous_function
src/topology/continuous_function/t0_sierpinski.lean
[ "topology.order", "topology.sets.opens", "topology.continuous_function.basic" ]
[ "embedding", "t0_space" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
units_lift : C(X, Mˣ) ≃ C(X, M)ˣ
{ to_fun := λ f, { val := ⟨λ x, f x, units.continuous_coe.comp f.continuous⟩, inv := ⟨λ x, ↑(f x)⁻¹, units.continuous_coe.comp (continuous_inv.comp f.continuous)⟩, val_inv := ext $ λ x, units.mul_inv _, inv_val := ext $ λ x, units.inv_mul _ }, inv_fun := λ f, { to_fun := λ x, ⟨f x, f⁻¹ x, continuous_m...
def
continuous_map.units_lift
topology.continuous_function
src/topology/continuous_function/units.lean
[ "analysis.normed_space.units", "algebra.algebra.spectrum", "topology.continuous_function.algebra" ]
[ "continuous", "continuous.prod_mk", "continuous_map.congr_fun", "inv_fun", "units.inv_mul", "units.mul_inv" ]
Equivalence between continuous maps into the units of a monoid with continuous multiplication and the units of the monoid of continuous maps.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
_root_.normed_ring.is_unit_unit_continuous {f : C(X, R)} (h : ∀ x, is_unit (f x)) : continuous (λ x, (h x).unit)
begin refine continuous_induced_rng.2 (continuous.prod_mk f.continuous (mul_opposite.continuous_op.comp (continuous_iff_continuous_at.mpr (λ x, _)))), have := normed_ring.inverse_continuous_at (h x).unit, simp only [←ring.inverse_unit, is_unit.unit_spec, ←function.comp_apply] at this ⊢, exact this.comp (f.c...
lemma
normed_ring.is_unit_unit_continuous
topology.continuous_function
src/topology/continuous_function/units.lean
[ "analysis.normed_space.units", "algebra.algebra.spectrum", "topology.continuous_function.algebra" ]
[ "continuous", "continuous.prod_mk", "is_unit", "is_unit.unit_spec", "normed_ring.inverse_continuous_at" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
units_of_forall_is_unit {f : C(X, R)} (h : ∀ x, is_unit (f x)) : C(X, Rˣ)
{ to_fun := λ x, (h x).unit, continuous_to_fun := normed_ring.is_unit_unit_continuous h }
def
continuous_map.units_of_forall_is_unit
topology.continuous_function
src/topology/continuous_function/units.lean
[ "analysis.normed_space.units", "algebra.algebra.spectrum", "topology.continuous_function.algebra" ]
[ "is_unit", "normed_ring.is_unit_unit_continuous" ]
Construct a continuous map into the group of units of a normed ring from a function into the normed ring and a proof that every element of the range is a unit.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
can_lift : can_lift C(X, R) C(X, Rˣ) (λ f, ⟨λ x, f x, units.continuous_coe.comp f.continuous⟩) (λ f, ∀ x, is_unit (f x))
{ prf := λ f h, ⟨units_of_forall_is_unit h, by { ext, refl }⟩ }
instance
continuous_map.can_lift
topology.continuous_function
src/topology/continuous_function/units.lean
[ "analysis.normed_space.units", "algebra.algebra.spectrum", "topology.continuous_function.algebra" ]
[ "can_lift", "is_unit" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_unit_iff_forall_is_unit (f : C(X, R)) : is_unit f ↔ ∀ x, is_unit (f x)
iff.intro (λ h, λ x, ⟨units_lift.symm h.unit x, rfl⟩) (λ h, ⟨(units_of_forall_is_unit h).units_lift, by { ext, refl }⟩)
lemma
continuous_map.is_unit_iff_forall_is_unit
topology.continuous_function
src/topology/continuous_function/units.lean
[ "analysis.normed_space.units", "algebra.algebra.spectrum", "topology.continuous_function.algebra" ]
[ "is_unit" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_unit_iff_forall_ne_zero (f : C(X, 𝕜)) : is_unit f ↔ ∀ x, f x ≠ 0
by simp_rw [f.is_unit_iff_forall_is_unit, is_unit_iff_ne_zero]
lemma
continuous_map.is_unit_iff_forall_ne_zero
topology.continuous_function
src/topology/continuous_function/units.lean
[ "analysis.normed_space.units", "algebra.algebra.spectrum", "topology.continuous_function.algebra" ]
[ "is_unit", "is_unit_iff_ne_zero" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
spectrum_eq_range (f : C(X, 𝕜)) : spectrum 𝕜 f = set.range f
begin ext, simp only [spectrum.mem_iff, is_unit_iff_forall_ne_zero, not_forall, coe_sub, pi.sub_apply, algebra_map_apply, algebra.id.smul_eq_mul, mul_one, not_not, set.mem_range, sub_eq_zero, @eq_comm _ x _] end
lemma
continuous_map.spectrum_eq_range
topology.continuous_function
src/topology/continuous_function/units.lean
[ "analysis.normed_space.units", "algebra.algebra.spectrum", "topology.continuous_function.algebra" ]
[ "algebra.id.smul_eq_mul", "algebra_map_apply", "mul_one", "not_forall", "not_not", "set.mem_range", "set.range", "spectrum", "spectrum.mem_iff" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
polynomial_functions_closure_eq_top' : (polynomial_functions I).topological_closure = ⊤
begin apply eq_top_iff.mpr, rintros f -, refine filter.frequently.mem_closure _, refine filter.tendsto.frequently (bernstein_approximation_uniform f) _, apply frequently_of_forall, intro n, simp only [set_like.mem_coe], apply subalgebra.sum_mem, rintro n -, apply subalgebra.smul_mem, dsimp [bernst...
theorem
polynomial_functions_closure_eq_top'
topology.continuous_function
src/topology/continuous_function/weierstrass.lean
[ "analysis.special_functions.bernstein", "topology.algebra.algebra" ]
[ "bernstein", "bernstein_approximation_uniform", "filter.tendsto.frequently", "polynomial_functions", "set_like.mem_coe", "subalgebra.smul_mem", "subalgebra.sum_mem" ]
The special case of the Weierstrass approximation theorem for the interval `[0,1]`. This is just a matter of unravelling definitions and using the Bernstein approximations.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
polynomial_functions_closure_eq_top (a b : ℝ) : (polynomial_functions (set.Icc a b)).topological_closure = ⊤
begin by_cases h : a < b, -- (Otherwise it's easy; we'll deal with that later.) { -- We can pullback continuous functions on `[a,b]` to continuous functions on `[0,1]`, -- by precomposing with an affine map. let W : C(set.Icc a b, ℝ) →ₐ[ℝ] C(I, ℝ) := comp_right_alg_hom ℝ ℝ (Icc_homeo_I a b h).symm.to_...
theorem
polynomial_functions_closure_eq_top
topology.continuous_function
src/topology/continuous_function/weierstrass.lean
[ "analysis.special_functions.bernstein", "topology.algebra.algebra" ]
[ "Icc_homeo_I", "algebra.comap_top", "polynomial_functions", "polynomial_functions.comap_comp_right_alg_hom_Icc_homeo_I", "polynomial_functions_closure_eq_top'", "set.Icc", "subalgebra.topological_closure_comap_homeomorph" ]
The **Weierstrass Approximation Theorem**: polynomials functions on `[a, b] ⊆ ℝ` are dense in `C([a,b],ℝ)` (While we could deduce this as an application of the Stone-Weierstrass theorem, our proof of that relies on the fact that `abs` is in the closure of polynomials on `[-M, M]`, so we may as well get this done first...
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
continuous_map_mem_polynomial_functions_closure (a b : ℝ) (f : C(set.Icc a b, ℝ)) : f ∈ (polynomial_functions (set.Icc a b)).topological_closure
begin rw polynomial_functions_closure_eq_top _ _, simp, end
theorem
continuous_map_mem_polynomial_functions_closure
topology.continuous_function
src/topology/continuous_function/weierstrass.lean
[ "analysis.special_functions.bernstein", "topology.algebra.algebra" ]
[ "polynomial_functions", "polynomial_functions_closure_eq_top", "set.Icc" ]
An alternative statement of Weierstrass' theorem. Every real-valued continuous function on `[a,b]` is a uniform limit of polynomials.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
exists_polynomial_near_continuous_map (a b : ℝ) (f : C(set.Icc a b, ℝ)) (ε : ℝ) (pos : 0 < ε) : ∃ (p : ℝ[X]), ‖p.to_continuous_map_on _ - f‖ < ε
begin have w := mem_closure_iff_frequently.mp (continuous_map_mem_polynomial_functions_closure _ _ f), rw metric.nhds_basis_ball.frequently_iff at w, obtain ⟨-, H, ⟨m, ⟨-, rfl⟩⟩⟩ := w ε pos, rw [metric.mem_ball, dist_eq_norm] at H, exact ⟨m, H⟩, end
theorem
exists_polynomial_near_continuous_map
topology.continuous_function
src/topology/continuous_function/weierstrass.lean
[ "analysis.special_functions.bernstein", "topology.algebra.algebra" ]
[ "continuous_map_mem_polynomial_functions_closure", "metric.mem_ball", "set.Icc" ]
An alternative statement of Weierstrass' theorem, for those who like their epsilons. Every real-valued continuous function on `[a,b]` is within any `ε > 0` of some polynomial.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
exists_polynomial_near_of_continuous_on (a b : ℝ) (f : ℝ → ℝ) (c : continuous_on f (set.Icc a b)) (ε : ℝ) (pos : 0 < ε) : ∃ (p : ℝ[X]), ∀ x ∈ set.Icc a b, |p.eval x - f x| < ε
begin let f' : C(set.Icc a b, ℝ) := ⟨λ x, f x, continuous_on_iff_continuous_restrict.mp c⟩, obtain ⟨p, b⟩ := exists_polynomial_near_continuous_map a b f' ε pos, use p, rw norm_lt_iff _ pos at b, intros x m, exact b ⟨x, m⟩, end
theorem
exists_polynomial_near_of_continuous_on
topology.continuous_function
src/topology/continuous_function/weierstrass.lean
[ "analysis.special_functions.bernstein", "topology.algebra.algebra" ]
[ "continuous_on", "exists_polynomial_near_continuous_map", "set.Icc" ]
Another alternative statement of Weierstrass's theorem, for those who like epsilons, but not bundled continuous functions. Every real-valued function `ℝ → ℝ` which is continuous on `[a,b]` can be approximated to within any `ε > 0` on `[a,b]` by some polynomial.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
zero_at_infty_continuous_map (α : Type u) (β : Type v) [topological_space α] [has_zero β] [topological_space β] extends continuous_map α β : Type (max u v)
(zero_at_infty' : tendsto to_fun (cocompact α) (𝓝 0))
structure
zero_at_infty_continuous_map
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[ "continuous_map", "topological_space" ]
`C₀(α, β)` is the type of continuous functions `α → β` which vanish at infinity from a topological space to a metric space with a zero element. When possible, instead of parametrizing results over `(f : C₀(α, β))`, you should parametrize over `(F : Type*) [zero_at_infty_continuous_map_class F α β] (f : F)`. When you ...
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
zero_at_infty_continuous_map_class (F : Type*) (α β : out_param $ Type*) [topological_space α] [has_zero β] [topological_space β] extends continuous_map_class F α β
(zero_at_infty (f : F) : tendsto f (cocompact α) (𝓝 0))
class
zero_at_infty_continuous_map_class
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[ "continuous_map_class", "topological_space" ]
`zero_at_infty_continuous_map_class F α β` states that `F` is a type of continuous maps which vanish at infinity. You should also extend this typeclass when you extend `zero_at_infty_continuous_map`.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coe_to_continuous_fun (f : C₀(α, β)) : (f.to_continuous_map : α → β) = f
rfl
lemma
zero_at_infty_continuous_map.coe_to_continuous_fun
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
ext {f g : C₀(α, β)} (h : ∀ x, f x = g x) : f = g
fun_like.ext _ _ h
lemma
zero_at_infty_continuous_map.ext
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[ "fun_like.ext" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
copy (f : C₀(α, β)) (f' : α → β) (h : f' = f) : C₀(α, β)
{ to_fun := f', continuous_to_fun := by { rw h, exact f.continuous_to_fun }, zero_at_infty' := by { simp_rw h, exact f.zero_at_infty' } }
def
zero_at_infty_continuous_map.copy
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[]
Copy of a `zero_at_infinity_continuous_map` with a new `to_fun` equal to the old one. Useful to fix definitional equalities.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coe_copy (f : C₀(α, β)) (f' : α → β) (h : f' = f) : ⇑(f.copy f' h) = f'
rfl
lemma
zero_at_infty_continuous_map.coe_copy
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
copy_eq (f : C₀(α, β)) (f' : α → β) (h : f' = f) : f.copy f' h = f
fun_like.ext' h
lemma
zero_at_infty_continuous_map.copy_eq
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[ "fun_like.ext'" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
eq_of_empty [is_empty α] (f g : C₀(α, β)) : f = g
ext $ is_empty.elim ‹_›
lemma
zero_at_infty_continuous_map.eq_of_empty
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[ "is_empty", "is_empty.elim" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
continuous_map.lift_zero_at_infty [compact_space α] : C(α, β) ≃ C₀(α, β)
{ to_fun := λ f, { to_fun := f, continuous_to_fun := f.continuous, zero_at_infty' := by simp }, inv_fun := λ f, f, left_inv := λ f, by { ext, refl }, right_inv := λ f, by { ext, refl } }
def
zero_at_infty_continuous_map.continuous_map.lift_zero_at_infty
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[ "compact_space", "inv_fun" ]
A continuous function on a compact space is automatically a continuous function vanishing at infinity.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
zero_at_infty_continuous_map_class.of_compact {G : Type*} [continuous_map_class G α β] [compact_space α] : zero_at_infty_continuous_map_class G α β
{ coe := λ g, g, coe_injective' := λ f g h, fun_like.coe_fn_eq.mp h, map_continuous := map_continuous, zero_at_infty := by simp }
def
zero_at_infty_continuous_map.zero_at_infty_continuous_map_class.of_compact
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[ "compact_space", "continuous_map_class", "zero_at_infty_continuous_map_class" ]
A continuous function on a compact space is automatically a continuous function vanishing at infinity. This is not an instance to avoid type class loops.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coe_zero [has_zero β] : ⇑(0 : C₀(α, β)) = 0
rfl
lemma
zero_at_infty_continuous_map.coe_zero
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
zero_apply [has_zero β] : (0 : C₀(α, β)) x = 0
rfl
lemma
zero_at_infty_continuous_map.zero_apply
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coe_mul [mul_zero_class β] [has_continuous_mul β] (f g : C₀(α, β)) : ⇑(f * g) = f * g
rfl
lemma
zero_at_infty_continuous_map.coe_mul
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[ "has_continuous_mul", "mul_zero_class" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mul_apply [mul_zero_class β] [has_continuous_mul β] (f g : C₀(α, β)) : (f * g) x = f x * g x
rfl
lemma
zero_at_infty_continuous_map.mul_apply
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[ "has_continuous_mul", "mul_zero_class" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coe_add [add_zero_class β] [has_continuous_add β] (f g : C₀(α, β)) : ⇑(f + g) = f + g
rfl
lemma
zero_at_infty_continuous_map.coe_add
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[ "add_zero_class", "has_continuous_add" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
add_apply [add_zero_class β] [has_continuous_add β] (f g : C₀(α, β)) : (f + g) x = f x + g x
rfl
lemma
zero_at_infty_continuous_map.add_apply
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[ "add_zero_class", "has_continuous_add" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
has_nat_scalar : has_smul ℕ C₀(α, β)
⟨λ n f, ⟨n • f, by simpa [coe_nsmul_rec] using zero_at_infty (nsmul_rec n f)⟩⟩
instance
zero_at_infty_continuous_map.has_nat_scalar
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[ "has_smul", "nsmul_rec" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
has_int_scalar : has_smul ℤ C₀(α, β)
⟨λ n f, ⟨n • f, by simpa using zero_at_infty (zsmul_rec n f)⟩⟩
instance
zero_at_infty_continuous_map.has_int_scalar
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[ "has_smul", "zsmul_rec" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coe_smul [has_zero β] {R : Type*} [has_zero R] [smul_with_zero R β] [has_continuous_const_smul R β] (r : R) (f : C₀(α, β)) : ⇑(r • f) = r • f
rfl
lemma
zero_at_infty_continuous_map.coe_smul
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[ "has_continuous_const_smul", "smul_with_zero" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
smul_apply [has_zero β] {R : Type*} [has_zero R] [smul_with_zero R β] [has_continuous_const_smul R β] (r : R) (f : C₀(α, β)) (x : α) : (r • f) x = r • f x
rfl
lemma
zero_at_infty_continuous_map.smul_apply
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[ "has_continuous_const_smul", "smul_with_zero" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
uniform_continuous (f : F) : uniform_continuous (f : β → γ)
(map_continuous f).uniform_continuous_of_tendsto_cocompact (zero_at_infty f)
lemma
zero_at_infty_continuous_map.uniform_continuous
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[ "uniform_continuous" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
bounded (f : F) : ∃ C, ∀ x y : α, dist ((f : α → β) x) (f y) ≤ C
begin obtain ⟨K : set α, hK₁, hK₂⟩ := mem_cocompact.mp (tendsto_def.mp (zero_at_infty (f : F)) _ (closed_ball_mem_nhds (0 : β) zero_lt_one)), obtain ⟨C, hC⟩ := (hK₁.image (map_continuous f)).bounded.subset_ball (0 : β), refine ⟨max C 1 + max C 1, (λ x y, _)⟩, have : ∀ x, f x ∈ closed_ball (0 : β) (max C 1),...
lemma
zero_at_infty_continuous_map.bounded
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[ "dist_triangle", "zero_lt_one" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
bounded_range (f : C₀(α, β)) : bounded (range f)
bounded_range_iff.2 f.bounded
lemma
zero_at_infty_continuous_map.bounded_range
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
bounded_image (f : C₀(α, β)) (s : set α) : bounded (f '' s)
f.bounded_range.mono $ image_subset_range _ _
lemma
zero_at_infty_continuous_map.bounded_image
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
to_bcf (f : C₀(α, β)) : α →ᵇ β
⟨f, map_bounded f⟩
def
zero_at_infty_continuous_map.to_bcf
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[]
Construct a bounded continuous function from a continuous function vanishing at infinity.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
to_bcf_injective : function.injective (to_bcf : C₀(α, β) → α →ᵇ β)
λ f g h, by { ext, simpa only using fun_like.congr_fun h x, }
lemma
zero_at_infty_continuous_map.to_bcf_injective
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[ "fun_like.congr_fun" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
dist_to_bcf_eq_dist {f g : C₀(α, β)} : dist f.to_bcf g.to_bcf = dist f g
rfl
lemma
zero_at_infty_continuous_map.dist_to_bcf_eq_dist
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
tendsto_iff_tendsto_uniformly {ι : Type*} {F : ι → C₀(α, β)} {f : C₀(α, β)} {l : filter ι} : tendsto F l (𝓝 f) ↔ tendsto_uniformly (λ i, F i) f l
by simpa only [metric.tendsto_nhds] using @bounded_continuous_function.tendsto_iff_tendsto_uniformly _ _ _ _ _ (λ i, (F i).to_bcf) f.to_bcf l
lemma
zero_at_infty_continuous_map.tendsto_iff_tendsto_uniformly
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[ "bounded_continuous_function.tendsto_iff_tendsto_uniformly", "filter", "metric.tendsto_nhds", "tendsto_uniformly" ]
Convergence in the metric on `C₀(α, β)` is uniform convergence.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
isometry_to_bcf : isometry (to_bcf : C₀(α, β) → α →ᵇ β)
by tauto
lemma
zero_at_infty_continuous_map.isometry_to_bcf
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[ "isometry" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
closed_range_to_bcf : is_closed (range (to_bcf : C₀(α, β) → α →ᵇ β))
begin refine is_closed_iff_cluster_pt.mpr (λ f hf, _), rw cluster_pt_principal_iff at hf, have : tendsto f (cocompact α) (𝓝 0), { refine metric.tendsto_nhds.mpr (λ ε hε, _), obtain ⟨_, hg, g, rfl⟩ := hf (ball f (ε / 2)) (ball_mem_nhds f $ half_pos hε), refine (metric.tendsto_nhds.mp (zero_at_infty g) (...
lemma
zero_at_infty_continuous_map.closed_range_to_bcf
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[ "add_halves", "cluster_pt_principal_iff", "dist_triangle_left", "half_pos", "is_closed" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
norm_to_bcf_eq_norm {f : C₀(α, β)} : ‖f.to_bcf‖ = ‖f‖
rfl
lemma
zero_at_infty_continuous_map.norm_to_bcf_eq_norm
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coe_star (f : C₀(α, β)) : ⇑(star f) = star f
rfl
lemma
zero_at_infty_continuous_map.coe_star
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
star_apply (f : C₀(α, β)) (x : α) : (star f) x = star (f x)
rfl
lemma
zero_at_infty_continuous_map.star_apply
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
comp (f : C₀(γ, δ)) (g : β →co γ) : C₀(β, δ)
{ to_continuous_map := (f : C(γ, δ)).comp g, zero_at_infty' := (zero_at_infty f).comp (cocompact_tendsto g) }
def
zero_at_infty_continuous_map.comp
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[]
Composition of a continuous function vanishing at infinity with a cocompact map yields another continuous function vanishing at infinity.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
coe_comp_to_continuous_fun (f : C₀(γ, δ)) (g : β →co γ) : ((f.comp g).to_continuous_map : β → δ) = f ∘ g
rfl
lemma
zero_at_infty_continuous_map.coe_comp_to_continuous_fun
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
comp_id (f : C₀(γ, δ)) : f.comp (cocompact_map.id γ) = f
ext (λ x, rfl)
lemma
zero_at_infty_continuous_map.comp_id
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[ "cocompact_map.id" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
comp_assoc (f : C₀(γ, δ)) (g : β →co γ) (h : α →co β) : (f.comp g).comp h = f.comp (g.comp h)
rfl
lemma
zero_at_infty_continuous_map.comp_assoc
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
zero_comp (g : β →co γ) : (0 : C₀(γ, δ)).comp g = 0
rfl
lemma
zero_at_infty_continuous_map.zero_comp
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
comp_add_monoid_hom [add_monoid δ] [has_continuous_add δ] (g : β →co γ) : C₀(γ, δ) →+ C₀(β, δ)
{ to_fun := λ f, f.comp g, map_zero' := zero_comp g, map_add' := λ f₁ f₂, rfl }
def
zero_at_infty_continuous_map.comp_add_monoid_hom
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[ "add_monoid", "has_continuous_add" ]
Composition as an additive monoid homomorphism.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
comp_mul_hom [mul_zero_class δ] [has_continuous_mul δ] (g : β →co γ) : C₀(γ, δ) →ₙ* C₀(β, δ)
{ to_fun := λ f, f.comp g, map_mul' := λ f₁ f₂, rfl }
def
zero_at_infty_continuous_map.comp_mul_hom
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[ "has_continuous_mul", "mul_zero_class" ]
Composition as a semigroup homomorphism.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
comp_linear_map [add_comm_monoid δ] [has_continuous_add δ] {R : Type*} [semiring R] [module R δ] [has_continuous_const_smul R δ] (g : β →co γ) : C₀(γ, δ) →ₗ[R] C₀(β, δ)
{ to_fun := λ f, f.comp g, map_add' := λ f₁ f₂, rfl, map_smul' := λ r f, rfl }
def
zero_at_infty_continuous_map.comp_linear_map
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[ "add_comm_monoid", "has_continuous_add", "has_continuous_const_smul", "module", "semiring" ]
Composition as a linear map.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
comp_non_unital_alg_hom {R : Type*} [semiring R] [non_unital_non_assoc_semiring δ] [topological_semiring δ] [module R δ] [has_continuous_const_smul R δ] (g : β →co γ) : C₀(γ, δ) →ₙₐ[R] C₀(β, δ)
{ to_fun := λ f, f.comp g, map_smul' := λ r f, rfl, map_zero' := rfl, map_add' := λ f₁ f₂, rfl, map_mul' := λ f₁ f₂, rfl }
def
zero_at_infty_continuous_map.comp_non_unital_alg_hom
topology.continuous_function
src/topology/continuous_function/zero_at_infty.lean
[ "topology.continuous_function.bounded", "topology.continuous_function.cocompact_map" ]
[ "has_continuous_const_smul", "module", "non_unital_non_assoc_semiring", "semiring", "topological_semiring" ]
Composition as a non-unital algebra homomorphism.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
fiber_bundle
(total_space_mk_inducing [] : ∀ (b : B), inducing (@total_space.mk B F E b)) (trivialization_atlas [] : set (trivialization F (π F E))) (trivialization_at [] : B → trivialization F (π F E)) (mem_base_set_trivialization_at [] : ∀ b : B, b ∈ (trivialization_at b).base_set) (trivialization_mem_atlas [] : ∀ b : B, triviali...
class
fiber_bundle
topology.fiber_bundle
src/topology/fiber_bundle/basic.lean
[ "topology.fiber_bundle.trivialization" ]
[ "inducing", "trivialization" ]
A (topological) fiber bundle with fiber `F` over a base `B` is a space projecting on `B` for which the fibers are all homeomorphic to `F`, such that the local situation around each point is a direct product.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mem_trivialization_atlas [fiber_bundle F E] (e : trivialization F (π F E)) : Prop
(out : e ∈ trivialization_atlas F E)
class
mem_trivialization_atlas
topology.fiber_bundle
src/topology/fiber_bundle/basic.lean
[ "topology.fiber_bundle.trivialization" ]
[ "fiber_bundle", "trivialization" ]
Given a type `E` equipped with a fiber bundle structure, this is a `Prop` typeclass for trivializations of `E`, expressing that a trivialization is in the designated atlas for the bundle. This is needed because lemmas about the linearity of trivializations or the continuity (as functions to `F →L[R] F`, where `F` is t...
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
map_proj_nhds (x : total_space F E) : map (π F E) (𝓝 x) = 𝓝 x.proj
(trivialization_at F E x.proj).map_proj_nhds $ (trivialization_at F E x.proj).mem_source.2 $ mem_base_set_trivialization_at F E x.proj
lemma
fiber_bundle.map_proj_nhds
topology.fiber_bundle
src/topology/fiber_bundle/basic.lean
[ "topology.fiber_bundle.trivialization" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
continuous_proj : continuous (π F E)
continuous_iff_continuous_at.2 $ λ x, (map_proj_nhds F x).le
lemma
fiber_bundle.continuous_proj
topology.fiber_bundle
src/topology/fiber_bundle/basic.lean
[ "topology.fiber_bundle.trivialization" ]
[ "continuous" ]
The projection from a fiber bundle to its base is continuous.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
is_open_map_proj : is_open_map (π F E)
is_open_map.of_nhds_le $ λ x, (map_proj_nhds F x).ge
lemma
fiber_bundle.is_open_map_proj
topology.fiber_bundle
src/topology/fiber_bundle/basic.lean
[ "topology.fiber_bundle.trivialization" ]
[ "is_open_map", "is_open_map.of_nhds_le" ]
The projection from a fiber bundle to its base is an open map.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
surjective_proj [nonempty F] : function.surjective (π F E)
λ b, let ⟨p, _, hpb⟩ := (trivialization_at F E b).proj_surj_on_base_set (mem_base_set_trivialization_at F E b) in ⟨p, hpb⟩
lemma
fiber_bundle.surjective_proj
topology.fiber_bundle
src/topology/fiber_bundle/basic.lean
[ "topology.fiber_bundle.trivialization" ]
[]
The projection from a fiber bundle with a nonempty fiber to its base is a surjective map.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
quotient_map_proj [nonempty F] : quotient_map (π F E)
(is_open_map_proj F E).to_quotient_map (continuous_proj F E) (surjective_proj F E)
lemma
fiber_bundle.quotient_map_proj
topology.fiber_bundle
src/topology/fiber_bundle/basic.lean
[ "topology.fiber_bundle.trivialization" ]
[ "quotient_map" ]
The projection from a fiber bundle with a nonempty fiber to its base is a quotient map.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
continuous_total_space_mk (x : B) : continuous (@total_space.mk B F E x)
(total_space_mk_inducing F E x).continuous
lemma
fiber_bundle.continuous_total_space_mk
topology.fiber_bundle
src/topology/fiber_bundle/basic.lean
[ "topology.fiber_bundle.trivialization" ]
[ "continuous" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mem_trivialization_at_proj_source {x : total_space F E} : x ∈ (trivialization_at F E x.proj).source
(trivialization.mem_source _).mpr $ mem_base_set_trivialization_at F E x.proj
lemma
fiber_bundle.mem_trivialization_at_proj_source
topology.fiber_bundle
src/topology/fiber_bundle/basic.lean
[ "topology.fiber_bundle.trivialization" ]
[ "trivialization.mem_source" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
trivialization_at_proj_fst {x : total_space F E} : ((trivialization_at F E x.proj) x).1 = x.proj
trivialization.coe_fst' _ $ mem_base_set_trivialization_at F E x.proj
lemma
fiber_bundle.trivialization_at_proj_fst
topology.fiber_bundle
src/topology/fiber_bundle/basic.lean
[ "topology.fiber_bundle.trivialization" ]
[ "trivialization.coe_fst'" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
continuous_within_at_total_space (f : X → total_space F E) {s : set X} {x₀ : X} : continuous_within_at f s x₀ ↔ continuous_within_at (λ x, (f x).proj) s x₀ ∧ continuous_within_at (λ x, ((trivialization_at F E (f x₀).proj) (f x)).2) s x₀
begin refine (and_iff_right_iff_imp.2 $ λ hf, _).symm.trans (and_congr_right $ λ hf, _), { refine (continuous_proj F E).continuous_within_at.comp hf (maps_to_image f s) }, have h1 : (λ x, (f x).proj) ⁻¹' (trivialization_at F E (f x₀).proj).base_set ∈ 𝓝[s] x₀ := hf.preimage_mem_nhds_within ((open_base_set _)....
lemma
fiber_bundle.continuous_within_at_total_space
topology.fiber_bundle
src/topology/fiber_bundle/basic.lean
[ "topology.fiber_bundle.trivialization" ]
[ "continuous_within_at", "continuous_within_at.comp", "continuous_within_at_prod_iff", "trivialization.coe_coe" ]
Characterization of continuous functions (at a point, within a set) into a fiber bundle.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
continuous_at_total_space (f : X → total_space F E) {x₀ : X} : continuous_at f x₀ ↔ continuous_at (λ x, (f x).proj) x₀ ∧ continuous_at (λ x, ((trivialization_at F E (f x₀).proj) (f x)).2) x₀
by { simp_rw [← continuous_within_at_univ], exact continuous_within_at_total_space F f }
lemma
fiber_bundle.continuous_at_total_space
topology.fiber_bundle
src/topology/fiber_bundle/basic.lean
[ "topology.fiber_bundle.trivialization" ]
[ "continuous_at", "continuous_within_at_univ" ]
Characterization of continuous functions (at a point) into a fiber bundle.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
fiber_bundle.exists_trivialization_Icc_subset [conditionally_complete_linear_order B] [order_topology B] [fiber_bundle F E] (a b : B) : ∃ e : trivialization F (π F E), Icc a b ⊆ e.base_set
begin classical, obtain ⟨ea, hea⟩ : ∃ ea : trivialization F (π F E), a ∈ ea.base_set := ⟨trivialization_at F E a, mem_base_set_trivialization_at F E a⟩, -- If `a < b`, then `[a, b] = ∅`, and the statement is trivial cases le_or_lt a b with hab hab; [skip, exact ⟨ea, by simp *⟩], /- Let `s` be the set of p...
lemma
fiber_bundle.exists_trivialization_Icc_subset
topology.fiber_bundle
src/topology/fiber_bundle/basic.lean
[ "topology.fiber_bundle.trivialization" ]
[ "bdd_above", "conditionally_complete_linear_order", "disjoint", "fiber_bundle", "is_lub", "is_lub_cSup", "is_open.mem_nhds", "is_open_Iio", "is_open_Ioi", "mem_nhds_within_Ici_iff_exists_mem_Ioc_Ico_subset", "mem_nhds_within_Iic_iff_exists_mem_Ico_Ioc_subset", "mem_nhds_within_of_mem_nhds", ...
If `E` is a fiber bundle over a conditionally complete linear order, then it is trivial over any closed interval.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
fiber_bundle_core (ι : Type*) (B : Type*) [topological_space B] (F : Type*) [topological_space F]
(base_set : ι → set B) (is_open_base_set : ∀ i, is_open (base_set i)) (index_at : B → ι) (mem_base_set_at : ∀ x, x ∈ base_set (index_at x)) (coord_change : ι → ι → B → F → F) (coord_change_self : ∀ i, ∀ x ∈ base_set i, ∀ v, coord_change i i x v = v) (continuous_on_coord_change : ∀ i j, continu...
structure
fiber_bundle_core
topology.fiber_bundle
src/topology/fiber_bundle/basic.lean
[ "topology.fiber_bundle.trivialization" ]
[ "continuous_on", "continuous_on_coord_change", "is_open", "topological_space" ]
Core data defining a locally trivial bundle with fiber `F` over a topological space `B`. Note that "bundle" is used in its mathematical sense. This is the (computer science) bundled version, i.e., all the relevant data is contained in the following structure. A family of local trivializations is indexed by a type `ι`, ...
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
index
ι
def
fiber_bundle_core.index
topology.fiber_bundle
src/topology/fiber_bundle/basic.lean
[ "topology.fiber_bundle.trivialization" ]
[]
The index set of a fiber bundle core, as a convenience function for dot notation
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
base
B
def
fiber_bundle_core.base
topology.fiber_bundle
src/topology/fiber_bundle/basic.lean
[ "topology.fiber_bundle.trivialization" ]
[]
The base space of a fiber bundle core, as a convenience function for dot notation
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
fiber (x : B)
F
def
fiber_bundle_core.fiber
topology.fiber_bundle
src/topology/fiber_bundle/basic.lean
[ "topology.fiber_bundle.trivialization" ]
[]
The fiber of a fiber bundle core, as a convenience function for dot notation and typeclass inference
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
topological_space_fiber (x : B) : topological_space (Z.fiber x)
‹topological_space F›
instance
fiber_bundle_core.topological_space_fiber
topology.fiber_bundle
src/topology/fiber_bundle/basic.lean
[ "topology.fiber_bundle.trivialization" ]
[ "topological_space" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
total_space
bundle.total_space F Z.fiber
def
fiber_bundle_core.total_space
topology.fiber_bundle
src/topology/fiber_bundle/basic.lean
[ "topology.fiber_bundle.trivialization" ]
[ "bundle.total_space" ]
The total space of the fiber bundle, as a convenience function for dot notation. It is by definition equal to `bundle.total_space Z.fiber`
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
proj : Z.total_space → B
bundle.total_space.proj
def
fiber_bundle_core.proj
topology.fiber_bundle
src/topology/fiber_bundle/basic.lean
[ "topology.fiber_bundle.trivialization" ]
[]
The projection from the total space of a fiber bundle core, on its base.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
triv_change (i j : ι) : local_homeomorph (B × F) (B × F)
{ source := (Z.base_set i ∩ Z.base_set j) ×ˢ univ, target := (Z.base_set i ∩ Z.base_set j) ×ˢ univ, to_fun := λp, ⟨p.1, Z.coord_change i j p.1 p.2⟩, inv_fun := λp, ⟨p.1, Z.coord_change j i p.1 p.2⟩, map_source' := λp hp, by simpa using hp, map_target' := λp hp, by simpa using hp, left_inv...
def
fiber_bundle_core.triv_change
topology.fiber_bundle
src/topology/fiber_bundle/basic.lean
[ "topology.fiber_bundle.trivialization" ]
[ "continuous_on.prod", "inv_fun", "is_open.inter", "is_open_univ", "local_homeomorph" ]
Local homeomorphism version of the trivialization change.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mem_triv_change_source (i j : ι) (p : B × F) : p ∈ (Z.triv_change i j).source ↔ p.1 ∈ Z.base_set i ∩ Z.base_set j
by { erw [mem_prod], simp }
lemma
fiber_bundle_core.mem_triv_change_source
topology.fiber_bundle
src/topology/fiber_bundle/basic.lean
[ "topology.fiber_bundle.trivialization" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
local_triv_as_local_equiv (i : ι) : local_equiv Z.total_space (B × F)
{ source := Z.proj ⁻¹' (Z.base_set i), target := Z.base_set i ×ˢ univ, inv_fun := λp, ⟨p.1, Z.coord_change i (Z.index_at p.1) p.1 p.2⟩, to_fun := λp, ⟨p.1, Z.coord_change (Z.index_at p.1) i p.1 p.2⟩, map_source' := λp hp, by simpa only [set.mem_preimage, and_true, set.mem_univ, set.prod_m...
def
fiber_bundle_core.local_triv_as_local_equiv
topology.fiber_bundle
src/topology/fiber_bundle/basic.lean
[ "topology.fiber_bundle.trivialization" ]
[ "inv_fun", "local_equiv", "set.mem_preimage", "set.mem_prod", "set.mem_univ", "set.prod_mk_mem_set_prod_eq" ]
Associate to a trivialization index `i : ι` the corresponding trivialization, i.e., a bijection between `proj ⁻¹ (base_set i)` and `base_set i × F`. As the fiber above `x` is `F` but read in the chart with index `index_at x`, the trivialization in the fiber above x is by definition the coordinate change from i to `inde...
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mem_local_triv_as_local_equiv_source (p : Z.total_space) : p ∈ (Z.local_triv_as_local_equiv i).source ↔ p.1 ∈ Z.base_set i
iff.rfl
lemma
fiber_bundle_core.mem_local_triv_as_local_equiv_source
topology.fiber_bundle
src/topology/fiber_bundle/basic.lean
[ "topology.fiber_bundle.trivialization" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
mem_local_triv_as_local_equiv_target (p : B × F) : p ∈ (Z.local_triv_as_local_equiv i).target ↔ p.1 ∈ Z.base_set i
by { erw [mem_prod], simp only [and_true, mem_univ] }
lemma
fiber_bundle_core.mem_local_triv_as_local_equiv_target
topology.fiber_bundle
src/topology/fiber_bundle/basic.lean
[ "topology.fiber_bundle.trivialization" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
local_triv_as_local_equiv_apply (p : Z.total_space) : (Z.local_triv_as_local_equiv i) p = ⟨p.1, Z.coord_change (Z.index_at p.1) i p.1 p.2⟩
rfl
lemma
fiber_bundle_core.local_triv_as_local_equiv_apply
topology.fiber_bundle
src/topology/fiber_bundle/basic.lean
[ "topology.fiber_bundle.trivialization" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
local_triv_as_local_equiv_trans (i j : ι) : (Z.local_triv_as_local_equiv i).symm.trans (Z.local_triv_as_local_equiv j) ≈ (Z.triv_change i j).to_local_equiv
begin split, { ext x, simp only [mem_local_triv_as_local_equiv_target] with mfld_simps, refl, }, { rintros ⟨x, v⟩ hx, simp only [triv_change, local_triv_as_local_equiv, local_equiv.symm, true_and, prod.mk.inj_iff, prod_mk_mem_set_prod_eq, local_equiv.trans_source, mem_inter_iff, and_true, mem_preimage, ...
lemma
fiber_bundle_core.local_triv_as_local_equiv_trans
topology.fiber_bundle
src/topology/fiber_bundle/basic.lean
[ "topology.fiber_bundle.trivialization" ]
[ "local_equiv.coe_mk", "local_equiv.coe_trans", "local_equiv.symm", "local_equiv.trans_source", "prod.mk.inj_iff" ]
The composition of two local trivializations is the trivialization change Z.triv_change i j.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
to_topological_space : topological_space Z.total_space
topological_space.generate_from $ ⋃ (i : ι) (s : set (B × F)) (s_open : is_open s), {(Z.local_triv_as_local_equiv i).source ∩ (Z.local_triv_as_local_equiv i) ⁻¹' s}
instance
fiber_bundle_core.to_topological_space
topology.fiber_bundle
src/topology/fiber_bundle/basic.lean
[ "topology.fiber_bundle.trivialization" ]
[ "is_open", "topological_space", "topological_space.generate_from" ]
Topological structure on the total space of a fiber bundle created from core, designed so that all the local trivialization are continuous.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
open_source' (i : ι) : is_open (Z.local_triv_as_local_equiv i).source
begin apply topological_space.generate_open.basic, simp only [exists_prop, mem_Union, mem_singleton_iff], refine ⟨i, Z.base_set i ×ˢ univ, (Z.is_open_base_set i).prod is_open_univ, _⟩, ext p, simp only [local_triv_as_local_equiv_apply, prod_mk_mem_set_prod_eq, mem_inter_iff, and_self, mem_local_triv_as_lo...
lemma
fiber_bundle_core.open_source'
topology.fiber_bundle
src/topology/fiber_bundle/basic.lean
[ "topology.fiber_bundle.trivialization" ]
[ "exists_prop", "is_open", "is_open_univ" ]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
local_triv (i : ι) : trivialization F Z.proj
{ base_set := Z.base_set i, open_base_set := Z.is_open_base_set i, source_eq := rfl, target_eq := rfl, proj_to_fun := λ p hp, by { simp only with mfld_simps, refl }, open_source := Z.open_source' i, open_target := (Z.is_open_base_set i).prod is_open_univ, continuous_to_fun := begin rw c...
def
fiber_bundle_core.local_triv
topology.fiber_bundle
src/topology/fiber_bundle/basic.lean
[ "topology.fiber_bundle.trivialization" ]
[ "continuous_on", "continuous_on_open_iff", "continuous_on_open_of_generate_from", "exists_prop", "is_open", "is_open_univ", "local_equiv.left_inv", "local_equiv.right_inv", "local_equiv.trans_source", "trivialization" ]
Extended version of the local trivialization of a fiber bundle constructed from core, registering additionally in its type that it is a local bundle trivialization.
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
local_triv_at (b : B) : trivialization F (π F Z.fiber)
Z.local_triv (Z.index_at b)
def
fiber_bundle_core.local_triv_at
topology.fiber_bundle
src/topology/fiber_bundle/basic.lean
[ "topology.fiber_bundle.trivialization" ]
[ "trivialization" ]
Preferred local trivialization of a fiber bundle constructed from core, at a given point, as a bundle trivialization
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
local_triv_at_def (b : B) : Z.local_triv (Z.index_at b) = Z.local_triv_at b
rfl
lemma
fiber_bundle_core.local_triv_at_def
topology.fiber_bundle
src/topology/fiber_bundle/basic.lean
[ "topology.fiber_bundle.trivialization" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
continuous_const_section (v : F) (h : ∀ i j, ∀ x ∈ (Z.base_set i) ∩ (Z.base_set j), Z.coord_change i j x v = v) : continuous (show B → Z.total_space, from λ x, ⟨x, v⟩)
begin apply continuous_iff_continuous_at.2 (λ x, _), have A : Z.base_set (Z.index_at x) ∈ 𝓝 x := is_open.mem_nhds (Z.is_open_base_set (Z.index_at x)) (Z.mem_base_set_at x), apply ((Z.local_triv_at x).to_local_homeomorph.continuous_at_iff_continuous_at_comp_left _).2, { simp only [(∘)] with mfld_simps, ...
lemma
fiber_bundle_core.continuous_const_section
topology.fiber_bundle
src/topology/fiber_bundle/basic.lean
[ "topology.fiber_bundle.trivialization" ]
[ "continuous", "continuous_at", "continuous_on", "continuous_on_const", "is_open.mem_nhds" ]
If an element of `F` is invariant under all coordinate changes, then one can define a corresponding section of the fiber bundle, which is continuous. This applies in particular to the zero section of a vector bundle. Another example (not yet defined) would be the identity section of the endomorphism bundle of a vector ...
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
local_triv_as_local_equiv_coe : ⇑(Z.local_triv_as_local_equiv i) = Z.local_triv i
rfl
lemma
fiber_bundle_core.local_triv_as_local_equiv_coe
topology.fiber_bundle
src/topology/fiber_bundle/basic.lean
[ "topology.fiber_bundle.trivialization" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
local_triv_as_local_equiv_source : (Z.local_triv_as_local_equiv i).source = (Z.local_triv i).source
rfl
lemma
fiber_bundle_core.local_triv_as_local_equiv_source
topology.fiber_bundle
src/topology/fiber_bundle/basic.lean
[ "topology.fiber_bundle.trivialization" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83
local_triv_as_local_equiv_target : (Z.local_triv_as_local_equiv i).target = (Z.local_triv i).target
rfl
lemma
fiber_bundle_core.local_triv_as_local_equiv_target
topology.fiber_bundle
src/topology/fiber_bundle/basic.lean
[ "topology.fiber_bundle.trivialization" ]
[]
https://github.com/leanprover-community/mathlib
65a1391a0106c9204fe45bc73a039f056558cb83