Bourbaki

Example

Tag 09KH, permanent. Cite it as [Bourbaki, Tag 09KH].

Integration, chapter VIII, § 4. Convolution of measures and functions

— 1) One can take f∈C(X)f \in \mathscr{C}(X), ν∈C′(X)\nu \in \mathscr{C}'(X) and μ∈C′(G)\mu \in \mathscr{C}'(G) by Prop. 3, and the Cor. of Prop. 5 of §1, No. 4. The formula (7) then means that the endomorphism ν↦(χ⋅μˇ)∗ν\nu \mapsto (\chi \cdot \check{\mu}) * \nu of C′(X)\mathscr{C}'(X) is the transpose of the endomorphism f↦μ∗ff \mapsto \mu * f of C(X)\mathscr{C}(X).

2) One can take f∈K(X)f \in \mathscr{K}(X), ν∈M(X)\nu \in \mathscr{M}(X) and μ∈C′(G)\mu \in \mathscr{C}'(G) by Prop. 3, Prop. 8 of §3, No. 2, and the remark that the support of the continuous function g(s,x)g(s, x) intersects the support of μ⊗ν\mu \otimes \nu in a compact set. The formula (7) then means that the endomorphism ν↦(χ⋅μˇ)∗ν\nu \mapsto (\chi \cdot \check{\mu}) * \nu of M(X)\mathscr{M}(X) is the transpose of the endomorphism f↦μ∗ff \mapsto \mu * f of K(X)\mathscr{K}(X).

3) If GG operates properly on XX, one can take f∈K(X)f \in \mathscr{K}(X), ν∈C′(X)\nu \in \mathscr{C}'(X) and μ∈M(G)\mu \in \mathscr{M}(G) by Prop. 4, Prop. 8 of §3, No. 2, and the same remark as in Example 2.

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

Cited by

Nothing.

Cites

Transcribed from the printed volume. Not translated.