|
We define extreme supercharacters of the infinite unitriangular group, introduce the ramification scheme associated with the classical supercharacter theories of the finite unitriangular groups and describe how extreme supercharacters of the infinite unitriangular group appear as weak limits of supercharacters of those. In order to prove that the set of extreme supercharacters is closed (with respect to the topology of weak convergence), we will deform the ramification sheme using appropriate operations of induction and restriction and show that the resulting scheme is multiplicative and determines a convenient Riesz ring. (Joint work with Filipe Gomes and Jocelyn Lochon.)
|
