Prelegent: GILLES GONÇALVES DE CASTRO

We build a universal C*-algebra using the strong operator topology to describe certain relations. In particular, this allows us to use infinite-sum relations. We show that these algebras have indeed a universal property, and then prove that the Exel-Laca algebras can be defined by considering infinite-sum relations analogous to the Cuntz-Krieger relations. Finally, we give sufficient conditions for when a C*-algebra generated by partial isometries and projections can be described as a universal C*-algebra using only norm relations. (Joint work with G. Boava.)