Universitat Autònoma de Barcelona
Date(s) : 21/03/2016 iCal
10 h 00 min - 11 h 00 min
In the seventies and eighties, Ahern, Clark, Cohn ans others proved several nice results on inner functions in Hardy Sobolev spaces or equivalently, in certain Besov spaces. The behavior of such functions is related to the behavior of sums of Poisson kernels. We will show that for $p>1/2$, one can describe the inner functions whose derivative is in the Hardy space $H^p$ in terms of the geometric location of its zeros. This is joint work, still in progress, with Janne Gröhn.