Coefficient systems and Jacquet modules

Abstract

Let F be a locally compact non-archimedean field and G the group of F-rational points of an algebraic group assumed to be defined over F, semisimple, simply connected and of F-rank 1. Let pi be a complex irreducible supercuspidal representation of G. We prove that pi is "nearly" induced in the following sense. There exist a maximal compact subgroup K of G and an irreducible smooth representation lamba of K such that pi contains lambda by restriction to K and such that the representation compactly induced from lambda to G is a finite direct sum of irreducible supercuspidal representations. The proof relies on the Schneider and Stuhler theory of equivariant coefficient systems and on a lemma on coefficient systems and Jacquet modules.