[Settfa] Tuesday 17/10, Tomasz Kania

kubis at math.cas.cz kubis at math.cas.cz
Thu Oct 12 15:00:02 CEST 2017


 ------------------------------------------------------------------------- 

 Tuesday 17th October, 10:00am 
 ------------------------------------------------------------------------- 

 Speaker:Tomasz Kania, IM CAS
 Title: The problem of uniform openness of convolution in group algebras

 Abstract  
The talk is a continuation of the talk given last week by Szymon Draga. We will focus on the proof of the theorem asserting that convolutions in group algebras of finite cyclic groups are not equi-uniformly open, which employs ultrapower techniques and relies on a theorem of S?siada about slender groups. As a result, we will derive the fact that neither the group algebra of the integers nor the group algebra of the rationals has uniformly open convolution. The mere openness of convolution in these algebras remains unknown. If time permits, we will draw some observations concerning openness of multiplication in the algebra of operators acting on a Banach space.

 For more information see the seminar web page at 
 https://calendar.math.cas.cz/set-theory-and-analysis-actual .



More information about the Settfa mailing list