[Settfa] Tuesday 02/05, Pawel Pietrzycki

[kubis at math.cas.cz]

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 Tuesday 2nd May, 10:50am 
 
  Place: IM in konírna 

 
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 Speaker:Pawel Pietrzycki, Jagiellonian University, Krakow, Poland
 Title: Arveson's hyperrigidity

 Abstract  

 Motivated both by the fundamental role of the classical Choquetboundary in classical approximation theory, and by the importance ofapproximation in the contemporary theory of operator algebras, Arvesonintroduced hyperrigidity as a form of approximation that captures manyimportant operator-algebraic phenomena.
 
I will discuss new results on the notion of hyperrigidity such as thecharacterization of spectral measures, the intertwining theorem, therelationship between the convergence of subnormal operators in weak andstrong operator topologies, and new examples of sets of generators thatare hyperrigid. The talk is based on joint works with Jan Stochel.
 

 
P. Pietrzycki, J. Stochel, Subnormal nth roots of quasinormal operators are quasinormal, J. Funct. Anal. 280 (2021) 109001.
 
P. Pietrzycki, J. Stochel, Two-moment characterization of spectral measureson the real line, Canadian Journal of Mathematics (2023).
 
P. Pietrzycki, J. Stochel, Hyperrigidity: characterizations of spectralmeasures and convergence of subnormal operators, in preparation.

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