[Settfa] Thursday 09/03, Piotr Nowakowski

[kubis at math.cas.cz]

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 Thursday 9th March, 10:00am 
 
  Place: IM in konírna 

 
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 Speaker:Piotr Nowakowski, University of Lodz, Poland
 Title: Spectre of a set

 Abstract  

 Let (X,+) be an Abelian group. Let A be a subset of X. We define the spectre of a set A as



S(A) := {x in X: for all y in A we have y+x in A or y-x in A}.


We will show some properties of the spectre of a set and its connections with centre of distance and achievement sets 



of absolutely convergent series.



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