Zero product preservers and orthogonality preservers on algebras of unbounded operators.
Zero spacing distributions for differenced L-functions
Zero sums of products of Toeplitz and Hankel operators on the Hardy space
On the Hardy space of the unit disk, we consider operators which are finite sums of products of a Toeplitz operator and a Hankel operator. We then give characterizations for such operators to be zero. Our results extend several known results using completely different arguments.
Zur Perron-Frobenius-Theorie stark stetiger Halbgruppen.