Antisymmetric elements in group rings with an orientation morphism

O. Broche, E. Jespers, M. Ruiz

Let $R$ be a commutative ring, $G$ a group and $RG$ its group ring. Let ${\varphi }_{\sigma }:RG\to RG$ denote the involution defined by ${\varphi }_{\sigma }(\sum r_{g}g)=\sum r_g\sigma (g)g^{-1}$, where $σ:G\t…