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TauCeti.Data.Bundle

Fibre-preserving maps of total spaces #

A map of total spaces Bundle.TotalSpace F₁ E₁ → Bundle.TotalSpace F₂ E₂ covering the identity of the base is determined by its fibre maps E₁ x → E₂ x. It is bijective exactly when each of its fibre maps is (TauCeti.bijective_totalSpace_map_iff). No topology or linear structure is involved.

theorem TauCeti.bijective_totalSpace_map_iff {B : Type u_1} {F₁ : Type u_2} {F₂ : Type u_3} {E₁ : B → Type u_4} {E₂ : B → Type u_5} {ϕ : (x : B) → E₁ x → E₂ x} :
(Function.Bijective fun (p : Bundle.TotalSpace F₁ E₁) => Bundle.TotalSpace.mk' F₂ p.proj (ϕ p.proj p.snd)) ↔ ∀ (x : B), Function.Bijective (ϕ x)

A fibre-preserving map of total spaces is bijective exactly when each of its fibre maps is.