Bourbaki

Proposition 2

Tag 01QD, permanent. Cite it as [Bourbaki, Tag 01QD].

Topologie algébrique, chapter I, § 5. Revêtements principaux

Let (E,p)(E, p) be a principal fibre space with base B and group G, and let ε\varepsilon be the section b↦(b,e)b\mapsto (b, e) of the trivial principal fibre space (B×G(B\times G, pr1)_1), where ee denotes the identity element of G. The mapping h↦h∘εh\mapsto h\circ \varepsilon is a bijection of CBG(B×G;E)\mathscr{C}_B^G(B\times G; E) onto the set S(B;E)\mathscr{S}(B; E) of continuous sections of pp. The inverse bijection associates to a continuous section ss of pp the B-morphism (b,g)↦s(b)⋅g(b, g)\mapsto s(b)\cdot g.

Bourbaki sets the proof directly after the statement, and the corpus does not separate them, so what is above is the statement and its proof together.

Cited by

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Cites

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Machine translation of the English, by gpt-5.4, against glossary version 34. Not checked by a person.