All proofs
Project-declaredLean 4.32.0-rc1 · mathlib@e752928d

Localisation stability

localisation_stability

Plain-language statement

Lemma lem:localisation_stability.

Exact Lean statement

theorem localisation_stability {f : M → M'} (ld : LocalisationData I I' f) :
    ∃ (ε : M → ℝ) (_hε : ∀ m, 0 < ε m) (_hε' : Continuous ε),
      ∀ (g : M → M') (_hg : ∀ m, dist (g m) (f m) < ε m) (i),
        range (g ∘ ld.φ i) ⊆ range (ld.ψj i)

Formal artifact

Lean source

Canonical source
Full Lean sourceLean 4
theorem localisation_stability {f : M  M'} (ld : LocalisationData I I' f) :     (ε : M  ) (_hε :  m, 0 < ε m) (_hε' : Continuous ε),       (g : M  M') (_hg :  m, dist (g m) (f m) < ε m) (i),        range (g ∘ ld.φ i)  range (ld.ψj i) := by  let K : ld.ι'  Set M' := fun i  ld.ψ i '' closedBall 0 1  let U : ld.ι'  Set M' := fun i  range <| ld.ψ i  have hK :  i, IsClosed (K i) := fun i     IsCompact.isClosed (IsCompact.image (isCompact_closedBall 0 1) (ld.ψ i).continuous)  have hK' : LocallyFinite K := ld.h₄.subset fun i  image_subset_range (ld.ψ i) (closedBall 0 1)  have hU :  i, IsOpen (U i) := fun i  (ld.ψ i).isOpen_range  have hKU :  i, K i  U i := fun i  image_subset_range _ _  obtain δ, hδ₀, hδ₁ := exists_continuous_real_forall_closedBall_subset hK hU hKU hK'  have := ld.cont  refine δ ∘ f, fun m  hδ₀ (f m), by fun_prop, fun g hg i  ?_  rintro - e, rfl  have hi : f (ld.φ i e)  K (ld.j i) :=    image_mono ball_subset_closedBall (ld.h₃ i (mem_range_self e))  exact hδ₁ (ld.j i) (f <| ld.φ i e) hi (le_of_lt (hg _))
Project
Sphere eversion
License
Apache-2.0
Commit
ded8fda5e76b
Source
SphereEversion/Global/LocalisationData.lean:129-146

Reuse this declaration

Bring the exact result into your workflow

The import identifies the source module. Your project still needs the pinned package dependency shown on this page.

What this badge means

This completion status comes from the project or community source. It has not yet been represented here as an independent rebuild and axiom audit.

Continue in this project

Related declarations

Project-declaredLean 4.32.0-rc1

Continuous of Path

Continuous.ofPath

Plain-language statement

Loop.ofPath is continuous, general version.

topologydifferential geometryhomotopy

Source project: Sphere eversion

Person-level attribution pending.

View proof record
Project-declaredLean 4.32.0-rc1

Injective update iff

DualPair.injective_update_iff

Project documentation

Map a dual pair under a linear equivalence. -/ @[simps] def map (p : DualPair E) (L : E ≃L[ℝ] E') : DualPair E' := ⟨p.π ∘L ↑L.symm, L p.v, (congr_arg p.π <| L.symm_apply_apply p.v).trans p.pairing⟩ theorem update_comp_left (p : DualPair E) (ψ' : F →L[ℝ] G) (φ : E →L[ℝ] F) (w : F) : p.update (ψ' ∘L φ) (ψ' w) = ψ' ∘L p.update φ w := by ext1 u simp only [upd...

topologydifferential geometryhomotopy

Source project: Sphere eversion

Person-level attribution pending.

View proof record
Project-declaredLean 4.32.0-rc1

Extend loops

extend_loops

Project documentation

A more precise version of sfHomotopy_in. -/ theorem sfHomotopy_in' {ι} (h₀ : SurroundingFamily g b γ₀ U) (h₁ : SurroundingFamily g b γ₁ U) (τ : ι → ℝ) (x : ι → E) (i : ι) {V : Set E} (hx : x i ∈ V) {t : ℝ} (ht : t ∈ I) {s : ℝ} (h_in₀ : ∀ i, x i ∈ V → ∀ t ∈ I, ∀ (s : ℝ), τ i ≠ 1 → (x i, γ₀ (x i) t s) ∈ Ω) (h_in₁ : ∀ i, x i ∈ V → ∀ t ∈ I, ∀ (s : ℝ), τ i ≠...

topologydifferential geometryhomotopy

Source project: Sphere eversion

Person-level attribution pending.

View proof record