# Juris Steprans: The descriptive set theoretic complexity of the weakly almost periodic functions in the dual of the group algebra

Place: Fields Institute,  Steart Library

Date and time : 7 November 2014,  13:30-15:00

Speaker:  Juris Steprans
Title: The descriptive set theoretic complexity of the weakly almost periodic functions in the dual of the group algebra

Abstract: The almost periodic functions on a group G are those functions F from G to the complex number such that the uniform norm closure of all shifts of F is compact in the uniform norm. The weakly almost periodic functions are those for which the analogous statement holds for the weak topology. The family of sets whose characteristic functions are weakly almost periodic forms a Boolean algebra. The question of when this family is a complete $\Pi^1_1$ set will be examined.