On the intersection of the spectrum of frequently hypercyclic operators with the unit circle
arXiv:1312.7465
Abstract
We exclude the existence of frequently hypercyclic operators that have a spectrum contained in the closed unit disc and that intersects the unit circle in only finitely many points under certain additional conditions. This extends a result of S. Shkarin, which states that the spectrum of a frequently hypercyclic operator cannot have isolated points.
Accepted for publication in Journal of Operator Theory