题 目：Groups and geometry
单 位：Department of Mathematics, KU Leuven, Belgium
时 间：2018年12月28日 下午16:00-17:00
摘 要：The representations of the fundamental group of an algebraicvariety form important topological invariants connecting group theorywith geometry. In this talk, we focus on the varieties of smallestnon-trivial dimension: curves. Using quivers and jet schemes, we showthat the geometry of the space of representations has constrainedsingularities. We apply this to show that the number of irreducible complexrepresentations of SL_n(Z) of dimension at most m grows at most as the square of m, for a fixed n>2.