Identity excluding groups

We consider the class of groups called identity excluding which has the property that any non-trivial irreducible unitary representation restricted to a dense subgroup does not weakly contain the trivial representation. For adapted and strictly aperiodic probability measures on these groups, it is known that the averages of unitary representations converge strongly. We show that motion group of a totally disconnected nilpotent group and certain class of p-adic algebraic groups which includes gruops whose solvable radical is type R are identity excluding. We also prove the convergence of averages of unitary representations for split solvable algebraic groups, which are not necessarily identity excluding.Comment: 13 page

On heredity of strongly proximal actions

We prove that action of a semigroup T on compact metric space X by continuous selfmaps is strongly proximal if and only if T action on P(X), the space of probability measures on $X$ with weak topology, is strongly proximal. As a consequence we prove that affine actions on certain compact convex subsets of finite-dimensional vector spaces are strongly proximal if and only if the action is proximal.Comment: 6pages. to appear in Archivum Math. (Brno) (2003