The tight groupoid of the inverse semigroups of left cancellative small categories

Abstract

We fix a path model for the space of filters of the inverse semigroup S_Λ associated to a left cancellative small category Λ. Then, we compute its tight groupoid, thus giving a representation of its C*-algebra as a (full) groupoid algebra. Using it, we characterize when these algebras are simple. Also, we determine amenability of the tight groupoid under mild, reasonable hypotheses.