GAMP seminar by Anna Kononova (Sct. Petersburg)
Speaker: Anna Kononova
Title: Outside the Szegö condition: some proofs and disproofs
Abstract: By the classical Szegö theorem the polynomials are dense in
L^2(mu), where mu is a measure on the unit circle, if and only
if the logarithmic integral of the density of mu diverges.
We will discuss several quantitative versions of this theorem for the
case of measure with a divergent logarithmic integral of its density.
As a by-product, we will disprove one conjecture of Nevai.
The talk will be based on joint work with A. Borichev and M. Sodin,
arXiv:1902.00874, arXiv:1902.00872.