[Settfa] Tuesday 08/11, Maciej Malicki

[kubis at math.cas.cz]

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 Tuesday 8th November, 10:00am 
 
  Place: IM in konírna 

 
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 Speaker:Maciej Malicki, Institute of Mathematics, Polish Academy of Sciences
 Title: Isomorphism of locally compact Polish metric structures

 Abstract  

 Gao and Kechris asked if the isometry relation on the space of locally compact Polish metric spaces is (Borel) reducible to the isomorphism relation on countable graphs. It turns out that this question is easier to deal with if it is translated into the language of metric structures and continuous logic. I prove that isomorphism on Borel classes of locally compact Polish metric structures is reducible to graph isomorphism, which immediately gives a positive answer to Gao and Kechris' question. I also analyse Borel isomorphism relations on such classes in terms of their reducibility to equality on hereditarily countable sets of appropriately bounded rank.

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