NBFAS meeting in Leeds, November 2nd and 3rd 2007


Dr Isabelle Chalendar, Université Lyon 1, France

Friday November 2nd, 1 pm

Introduction to Hardy spaces and Blaschke products    Handout (PDF)


Prof. Pamela Gorkin, Bucknell University, USA

Friday November 2nd, 2:30 pm

What interpolating Blaschke products can do

Blaschke products play an important role in the study of bounded analytic functions. An equally important role is played by a much smaller class of functions: the interpolating Blaschke products. Interpolating Blaschke products have zero sequences that are separated in a very natural way, while a general Blaschke product does not. Yet, it seems that interpolating Blaschke products are more flexible than might be expected. In this talk, we begin with an overview of the current literature of the work on interpolation and interpolating Blaschke products, including a look at the role such products have played in the study of bounded analytic functions and some recent results on approximation by interpolating Blaschke products.

Friday November 2nd, 4 pm

What interpolating Blaschke products cannot do

In this talk we look at some other problems that have sparked recent work in this area and we take a closer look at a surprising new class of Blaschke products, the so-called WEP Blaschke products. We discuss some of the known properties of these functions that suggest they act like. finite products of interpolating Blaschke products and we show that there exist WEP Blaschke products that are not finite products of interpolating Blaschke products. We conclude this talk with some new open questions in this area.

Prof. Stefaan Vaes, Katholieke Universiteit Leuven, Belgium

Saturday, November 3rd, 9.30 am and 11 am

Rigidity results for von Neumann algebras and Bernoulli actions    Handout 1 (PDF)    Handout 2 (PDF)

Group actions on probability spaces give rise to von Neumann algebras through the group measure space construction of Murray and von Neumann. Recently, Sorin Popa has introduced very powerful techniques allowing in certain cases to recover the group and the action from the associated von Neumann algebra. After an introduction to the theory of II_1 factors and group actions, I will present the proof of Popa's orbit equivalence superrigidity theorem for Bernoulli actions as well as a survey of my recent work on the computation of all finite index bimodules for a family of II_1 factors.

Anybody interested was welcome to attend. The meeting took place in MALL 1, School of Mathematics, University of Leeds. (There are campus maps here and a list of hotels here.) NBFAS has some limited support available for postgraduate students to attend.

Sandra Pott, NBFAS Secretary.

PDF version of this notice

The address of this page is http://www.maths.leeds.ac.uk/nbfas/leeds07.html

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