All Questions

Fix $k$ a commutative ring (or, if more convenient, assume it’s a field or even an algebraically closed field of characteristic 0, which is the case I’m mainly interested in). Let $A$ be a unital ...

Let $k=\mathbb C$, let $K$ be a finite extension of the field $k(X_1,X_2,X_3)$ of rational functions in $3$ variables, let $L/K$ be a finite Galois extension of commutative fields and let the Galois ...

Can someone provide a reference for the following Maschke lemma: If $C$ is a semisimple algebra over a field of characteristic zero and $G$ is a finite group acting on $C$ by automorphisms, then $C \...