Bourbaki

Proposition 6

Tag 0CB9, permanent. Cite it as [Bourbaki, Tag 0CB9].

General Topology, chapter X, § 1. The uniformity of $\mathscr{G}$-convergence

Let XX be a topological space, YY a uniform space and G\mathscr{G} a set of subsets of XX. For each A∈GA \in \mathscr{G} and each closed entourage VV of YY, the traces on C(X;Y)×C(X;Y)\mathscr{C}(X; Y) \times \mathscr{C}(X; Y) of W(A,V)W(A, V) and W(A‾,V)W(\overline{A}, V) are the same.

For if u,vu, v are continuous mappings of XX into YY, the mapping x↦(u(x),v(x))x \mapsto (u(x), v(x)) of XX into Y×YY \times Y is continuous, and the hypothesis that (u(x),v(x))∈V(u(x), v(x)) \in V for all x∈Ax \in A therefore implies that (u(x),v(x))∈V‾=V(u(x), v(x)) \in \overline{V} = V for all x∈A‾x \in \overline{A} (Chapter I, § 2, no. 1, Theorem 1).

If Gˉ\bar{\mathscr{G}} denotes the set of closures in XX of the sets of G\mathscr{G}, Proposition 6 shows that, on C(X;Y)\mathscr{C}(X; Y), the structures of G\mathscr{G}-convergence and Gˉ\bar{\mathscr{G}}-convergence are identical.

G-convergence in spaces of continuous mappings

Bourbaki puts the proof directly after the statement, so what is above is the statement and its proof together.

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Cites

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