Noether?s problem for dihedral 2-groups
Noether?s problem for dihedral 2-groups
Let $K$ be any field and $G$ be a finite group. Let $G$ act on the rational function field $K(x\_g: , g \in G)$ by $K$-automorphisms defined by $g \cdot x\_h= x \_{gh}$ for any $g, , h \in G$. Denote by $K(G)$ the fixed field $K(x\_g: , g \in …