Date:	Tue, May 7, 2013
Time:	14:15
Place:	Research I Seminar Room

Abstract: An old theorem of Milnor and Wolf states that the word growth function of a finitely generated solvable group is either polynomial or exponential. In the case of exponential growth, Rosenblatt proved that the group always contains a copy of the free semigroup on two generators. I will talk about various extensions of this theorem, in particular the existence of dense free semigroups (in various topologies) and random free semigroups.