Johannes Kepler Symposium on Mathematics

As part of the Johannes Kepler symposium on mathematics Dr. Petro Yudytskiy, Institut für Analysis, JKU Linz, will give a public talk (followed by a discussion) on Wed, May 11, 2011 at 15:15 o'clock at HS 13 on the topic of "Uniform approximation of sgn(x) by polynomials and entire functions " . The organziers of the symposium,

O.Univ.-Prof. Dr. Ulrich Langer,
Univ.-Prof. Dr. Gerhard Larcher
A.Univ.-Prof. Dr. Jürgen Maaß, and
die ÖMG (Österreichische Mathematische Gesellschaft),

hereby cordially invite you.

Series B - Mathematical Colloquium:

The intention is to present new mathematical results for an audience interested in general mathematics.

Uniform approximation of sgn(x) by polynomials and entire functions

We study the best uniform approximation by polynomials of fixed degree of the function sgn(x) on the union of two intervals. We obtain precise asymptotics, with explicit constants, for the error of the best approximation as the degrees tend to infinity. Our approach is based on a new representation of the extremal polynomials in terms of certain conformal maps