Bourbaki

Proposition 11

Tag 02R8, permanent. Cite it as [Bourbaki, Tag 02R8].

Théories spectrales, chapter III, § 2. Exemples d’applications linéaires compactes

Suppose that the vector bundle E is locally of finite rank. Let Y be an open relatively compact subset of X. The restriction mapping f↦f∣Yf\mapsto f|Y of Sω(X;E)\mathscr{S}^{\omega}(X; E) into Sω(Y;E)\mathscr{S}^{\omega}(Y; E) is compact.

With the notation of lemma 5, one has a commutative diagram

Sω(X;E)←i→S1(X0;E0) \mathscr{S}^{\omega}(X; E)\leftarrow_i\rightarrow \mathscr{S}^1(X_0; E_0)
→←u→←v(3) \rightarrow \leftarrow_u\rightarrow \leftarrow_v \tag{3}
Sω(Y;E)←j→S0(Y0;E0) \mathscr{S}^{\omega}(Y; E)\leftarrow_j\rightarrow \mathscr{S}^0(Y_0; E_0)

where ii and jj are the canonical injections and u,vu,v the restriction mappings. The mapping ii is continuous (Lemma 5, b)), and the mapping uu is compact (Proposition 10). Since the canonical injection jj is continuous, strict, and has closed image (Lemma 5, a)), the mapping uu is compact (Remark 5 of III, p. 3).

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.

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Cites

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Machine translation of the English, by gpt-5.4, gpt-5-6-mini, against glossary version 34. Not checked by a person. That model is a cut down version of the one the rest of this language was written by.