Bourbaki

Definition 1

Tag 06CT, permanent. Cite it as [Bourbaki, Tag 06CT].

Algebra, chapter IV, § 5. Symmetric tensors and polynomial mappings

— If G is of finite index in H, we denote by TrH/G\mathrm{Tr}_{H/G} the mapping of MGM^G into MHM^H defined by

TrH/Gm=∑x∈H/Gxm. \mathrm{Tr}_{H/G} m = \sum_{x \in H/G} x m .

This mapping is a homomorphism of the A-module MGM^G into the A-module MHM^H.

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

Cited by

Nothing.

Cites

Nothing.

Transcribed from the printed edition, 2003, Springer. Not translated.