Equivariant representation theory for proper actions on discrete spaces

Abstract: Starting from any proper action of any locally compact quantum group on any discrete quantum space, we show that its equivariant representation theory yields a concrete unitary 2-category of finite type Hilbert bimodules over the discrete quantum space, from which the quantum group and its action may be completely reconstructed as in a previous article by the author. In particular, this shows that any locally compact quantum group acting properly on a discrete quantum space must be an algebraic quantum group.