Best Rational Approximation of Functions with Singularities

Add to your list(s) Download to your calendar using vCal

• Alexander Pushnitski (King's College London)
• Monday 12 October 2015, 16:00-17:00
• Lecture Theatre 4, Strathcona Building.

If you have a question about this talk, please contact Alessio Martini.

I will recall some background facts on the problem of polynomial and rational approximation of functions with singularities. Then I will report the results of my recent work with Dmitri Yafaev (University of Rennes-1). We consider functions omega on the unit circle with a finite number of logarithmic singularities. We study the approximation of omega by rational functions in the BMO norm. We find the leading term of the asymptotics of the distance in the BMO norm between omega and the set of rational functions of degree n as n goes to infinity. Our approach relies on the Adamyan-Arov-Krein theorem and on the study of the asymptotic behaviour of singular values of Hankel operators.

This talk is part of the Analysis seminar series.

This talk is included in these lists:

• Analysis seminar
• Lecture Theatre 4, Strathcona Building
• School of Mathematics events

Note that ex-directory lists are not shown.